Randomisation to protect against selection bias in healthcare trials

Drug trials are more likely to disclose full placebo control information than non-drug trials: A cross-sectional study of participant information leaflets of placebo-controlled trials

Background

This study aimed to investigate whether placebo control is differently disclosed in drug and non-drug randomised clinical trial (RCT) participant information leaflets (PILs) and how this might affect participant blinding and direction of study outcomes.

Methods

PILs were obtained from trials registered in the International Standard Randomised Controlled Trial Number database via email. Placebo descriptions in PILs were categorised as Full Disclosure (FD), Partial Disclosure (PD), or Missing Information (MI). Associations between intervention type (drug or non-drug)/placebo disclosure (FD or PD/MI) and participant blinding success/trial outcome direction (positive or non-positive) were examined using a two-sided Fisher's exact test.

Results

Of 116 collected PILs, 56 % were for drug trials and 44 % were for non-drug trials. Among them, 88 PILs had the corresponding publications available and 68 reports specified primary outcomes. Drug trials were more likely to fully disclose placebo information than non-drug trials (92.3 % vs. 74.5 %, p < 0.05). However, the success rate of blinding was only reported in 3 out of 88 trial publications (3.4 %), precluding further analysis. Furthermore, there was no significant association between the direction of trial results and the type of intervention or placebo disclosure.

Conclusion

Our study findings suggest that drug and non-drug RCTs might differ in the way they reveal placebo control information. Further research is warranted to understand what leads to more common PD of placebo information in non-drug trials than drug trials and to determine the optimal placebo control disclosure in specific trial context.

Effectiveness of Motor Imagery in the Rehabilitation of People With Parkinson's Disease: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

With more research completed using Motor imagery (MI) in people with Parkinson's disease, this study gathered and synthesized evidence on the use of MI for Parkinson's disease in improving rehabilitation outcomes.

METHODS

Medical Literature Analysis and Retrieval System Online, Embase, Web of Science, The Cochrane Library, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and Scopus were searched from inception to May 2023. We included randomized controlled trials that examine the effects of MI on individuals with Parkinson's disease. Two reviewers selected articles and extracted study characteristics and results independently. The Physiotherapy Evidence Database scale was used to assess the methodological quality. Mean differences and 95% confidence intervals were calculated. Heterogeneity was assessed using the I2 statistic.

RESULTS

Thirteen articles with 12 studies were included, involving 320 individuals with Parkinson's disease, with moderate to high methodological quality (mean = 6.62/10). Compared with the control group, 3 articles reported significant greater improvements in cognitive function, 7 reported significant greater improvement in motor function, 1 article reported significant greater improvement in quality of life, and 1 reported significant greater confidence in daily task performance. No statistically significant effects were found in the meta-analyses. Conclusion. Results of individual articles were in favor of the MI intervention. No statistically significant results were found in the meta-analyses. This might be due to the small number of studies and the heterogeneity of interventions and outcome measures used. MI may be effective in improving some rehabilitation outcomes, but meta-analytic evidence is lacking. More research with larger sample size and less heterogeneous samples, interventions, and outcome measures, is warranted.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42021230556.

Application of the Composite Quality Score (CQS-2B) versus Cochrane's Risk of Bias tool (Version 2) in systematic reviews of clinical trials - an exploratory study

Objectives

To explore whether systematic review conclusions generated from Cochrane's second version of its Risk of Bias tool (RoB 2) for trial appraisal differ when the Composite Quality Score, Version 2.B (CQS-2B) is used instead and to develop a testable hypothesis based on these findings.

Methods

PubMed was searched for one single systematic review. From the review's accepted trials, data concerning effect estimates and overall bias risk according to the RoB 2 tool were extracted. All trial reports were appraised again using the CQS-2B. Datasets were stratified according to overall bias risk (RoB 2) or corroboration (C-) level (CQS-2B). The effect estimates from trials with 'low bias risk' (RoB 2) and with highest C-level (CQS-2B) were pooled separately. These pooled effect estimates were statistically and all clinical conclusions qualitatively compared.

Results

The pooled effect estimates for trials with 'low bias risk' (RoB 2) were -0.07, 95% CI: -0.10 to -0.04 (I2 = 0.0%) and for the highest C-levels (CQS-2B) 0.08, 95% CI: -0.12 to -0.04 (I2 = 57.0%). The difference was statistically not significant (p = 0.70). Contrary to the RoB 2 tool, no clinical conclusions in line with the CQS-2B were made, because the effect estimates were judged to be erroneously overestimated, due to high risk of bias.

Conclusion

A testable hypothesis was generated suggesting that trial appraisal using the CQS-2B may provide more conservative conclusions based on similar data than with the RoB 2 tool.

Time to level up: A systematic review of interventions aiming to reduce stigma toward autistic people

LAY ABSTRACT

How non-autistic people think about autistic people impacts autistic people negatively. Many studies developed trainings to reduce autism stigma. The existing trainings vary a lot in terms of study design, content, and reported effectiveness. This means that a review studying how the studies have been conducted is needed. We also looked at the quality of these studies. We collected and studied 26 studies that tried to reduce stigma toward autistic people. The studies often targeted White K-12 students and college students. Most trainings were implemented once. Trainings frequently used video or computer. Especially, recent studies tended to use online platforms. The study quality was poor for most studies. Some studies made inaccurate claims about the intervention effectiveness. Studies did not sufficiently address study limitations. Future trainings should aim to figure out why and how interventions work. How intervention changes people's behavior and thoughts should be studied. Researchers should study whether the training can change the societal stigma. Also, researchers should use a better study design.

To weight or not to weight? Studying the effect of selection bias in three large EHR-linked biobanks

Objective

To explore the role of selection bias adjustment by weighting electronic health record (EHR)-linked biobank data for commonly performed analyses.

Materials and methods

We mapped diagnosis (ICD code) data to standardized phecodes from three EHR-linked biobanks with varying recruitment strategies: All of Us (AOU; n=244,071), Michigan Genomics Initiative (MGI; n=81,243), and UK Biobank (UKB; n=401,167). Using 2019 National Health Interview Survey data, we constructed selection weights for AOU and MGI to be more representative of the US adult population. We used weights previously developed for UKB to represent the UKB-eligible population. We conducted four common descriptive and analytic tasks comparing unweighted and weighted results.

Results

For AOU and MGI, estimated phecode prevalences decreased after weighting (weighted-unweighted median phecode prevalence ratio [MPR]: 0.82 and 0.61), while UKB's estimates increased (MPR: 1.06). Weighting minimally impacted latent phenome dimensionality estimation. Comparing weighted versus unweighted PheWAS for colorectal cancer, the strongest associations remained unaltered and there was large overlap in significant hits. Weighting affected the estimated log-odds ratio for sex and colorectal cancer to align more closely with national registry-based estimates.

Discussion

Weighting had limited impact on dimensionality estimation and large-scale hypothesis testing but impacted prevalence and association estimation more. Results from untargeted association analyses should be followed by weighted analysis when effect size estimation is of interest for specific signals.

Conclusion

EHR-linked biobanks should report recruitment and selection mechanisms and provide selection weights with defined target populations. Researchers should consider their intended estimands, specify source and target populations, and weight EHR-linked biobank analyses accordingly.

Healthcare outcomes assessed with observational study designs compared with those assessed in randomized trials: a meta-epidemiological study

BACKGROUND

Researchers and decision-makers often use evidence from randomised controlled trials (RCTs) to determine the efficacy or effectiveness of a treatment or intervention. Studies with observational designs are often used to measure the effectiveness of an intervention in 'real world' scenarios. Numerous study designs and their modifications (including both randomised and observational designs) are used for comparative effectiveness research in an attempt to give an unbiased estimate of whether one treatment is more effective or safer than another for a particular population. An up-to-date systematic analysis is needed to identify differences in effect estimates from RCTs and observational studies. This updated review summarises the results of methodological reviews that compared the effect estimates of observational studies with RCTs from evidence syntheses that addressed the same health research question.

OBJECTIVES

To assess and compare synthesised effect estimates by study type, contrasting RCTs with observational studies. To explore factors that might explain differences in synthesised effect estimates from RCTs versus observational studies (e.g. heterogeneity, type of observational study design, type of intervention, and use of propensity score adjustment). To identify gaps in the existing research comparing effect estimates across different study types.

SEARCH METHODS

We searched MEDLINE, the Cochrane Database of Systematic Reviews, Web of Science databases, and Epistemonikos to May 2022. We checked references, conducted citation searches, and contacted review authors to identify additional reviews.

SELECTION CRITERIA

We included systematic methodological reviews that compared quantitative effect estimates measuring the efficacy or effectiveness of interventions tested in RCTs versus in observational studies. The included reviews compared RCTs to observational studies (including retrospective and prospective cohort, case-control and cross-sectional designs). Reviews were not eligible if they compared RCTs with studies that had used some form of concurrent allocation.

DATA COLLECTION AND ANALYSIS

Using results from observational studies as the reference group, we examined the relative summary effect estimates (risk ratios (RRs), odds ratios (ORs), hazard ratios (HRs), mean differences (MDs), and standardised mean differences (SMDs)) to evaluate whether there was a relatively larger or smaller effect in the ratio of odds ratios (ROR) or ratio of risk ratios (RRR), ratio of hazard ratios (RHR), and difference in (standardised) mean differences (D(S)MD). If an included review did not provide an estimate comparing results from RCTs with observational studies, we generated one by pooling the estimates for observational studies and RCTs, respectively. Across all reviews, we synthesised these ratios to produce a pooled ratio of ratios comparing effect estimates from RCTs with those from observational studies. In overviews of reviews, we estimated the ROR or RRR for each overview using observational studies as the reference category. We appraised the risk of bias in the included reviews (using nine criteria in total). To receive an overall low risk of bias rating, an included review needed: explicit criteria for study selection, a complete sample of studies, and to have controlled for study methodological differences and study heterogeneity. We assessed reviews/overviews not meeting these four criteria as having an overall high risk of bias. We assessed the certainty of the evidence, consisting of multiple evidence syntheses, with the GRADE approach.

MAIN RESULTS

We included 39 systematic reviews and eight overviews of reviews, for a total of 47. Thirty-four of these contributed data to our primary analysis. Based on the available data, we found that the reviews/overviews included 2869 RCTs involving 3,882,115 participants, and 3924 observational studies with 19,499,970 participants. We rated 11 reviews/overviews as having an overall low risk of bias, and 36 as having an unclear or high risk of bias. Our main concerns with the included reviews/overviews were that some did not assess the quality of their included studies, and some failed to account appropriately for differences between study designs - for example, they conducted aggregate analyses of all observational studies rather than separate analyses of cohort and case-control studies. When pooling RORs and RRRs, the ratio of ratios indicated no difference or a very small difference between the effect estimates from RCTs versus from observational studies (ratio of ratios 1.08, 95% confidence interval (CI) 1.01 to 1.15). We rated the certainty of the evidence as low. Twenty-three of 34 reviews reported effect estimates of RCTs and observational studies that were on average in agreement. In a number of subgroup analyses, small differences in the effect estimates were detected: - pharmaceutical interventions only (ratio of ratios 1.12, 95% CI 1.04 to 1.21); - RCTs and observational studies with substantial or high heterogeneity; that is, I2 ≥ 50% (ratio of ratios 1.11, 95% CI 1.04 to 1.18); - no use (ratio of ratios 1.07, 95% CI 1.03 to 1.11) or unclear use (ratio of ratios 1.13, 95% CI 1.03 to 1.25) of propensity score adjustment in observational studies; and - observational studies without further specification of the study design (ratio of ratios 1.06, 95% CI 0.96 to 1.18). We detected no clear difference in other subgroup analyses.

AUTHORS' CONCLUSIONS

We found no difference or a very small difference between effect estimates from RCTs and observational studies. These findings are largely consistent with findings from recently published research. Factors other than study design need to be considered when exploring reasons for a lack of agreement between results of RCTs and observational studies, such as differences in the population, intervention, comparator, and outcomes investigated in the respective studies. Our results underscore that it is important for review authors to consider not only study design, but the level of heterogeneity in meta-analyses of RCTs or observational studies. A better understanding is needed of how these factors might yield estimates reflective of true effectiveness.

A Systematic Review and Meta-Analysis of Xiangsha Liujunzi Decoction in the Treatment of Chronic Gastritis

BACKGROUND

Chronic gastritis (CG) is characterized by inflammation of the gastric mucosa, which can progress to atrophic gastritis, intestinal metaplasia, and dysplasia. Xiangsha Liujunzi Decoction (XSLJZD), a classic traditional Chinese medicine prescription commonly used to treat digestive system diseases, is widely used to treat CG. Therefore, it is necessary to systematically evaluate the efficacy and safety of XSLJZD in the treatment of CG.

METHODS

Chinese and English databases were searched, and randomized controlled trials of XSLJZD for the treatment of CG were collected from the establishment of the databases to December 28, 2022. Studies were screened according to inclusion and exclusion criteria. The methodological quality of the included studies was assessed using the risk-of-bias assessment tool in the Cochrane Handbook. Data from the included studies were extracted, and a meta-analysis was performed using Review Manager 5.3 and Stata 15.1. Finally, funnel plots and Egger's tests were used to assess publication bias.

RESULTS

Fourteen studies with a sample size of 1434 cases. XSLJZD has more advantages than conventional treatment in the treatment of CG, as it can improve the clinical cure rate, clinical efficacy rate, efficacy rate of endoscopic examination, recurrence rate, and TCM symptom scores, and is relatively safe. Funnel plots and Egger's tests indicated publication bias in the included studies.

CONCLUSION

The results of the meta-analysis showed that XSLJZD has advantages in treating CG compared with conventional treatment and is relatively safe. However, owing to the limitations in the quality and quantity of the included studies, caution is recommended when generalizing and applying these results. Further high-quality studies are needed to confirm these findings.

Prehabilitation programs for individuals with cancer: a systematic review of randomized-controlled trials

BACKGROUND

Prehabilitation programs focusing on exercise training as the main component are known as a promising alternative for improving patients' outcomes before cancer surgery. This systematic review determined the benefits and harms of prehabilitation programs compared with usual care for individuals with cancer.

METHODS

We searched CENTRAL, MEDLINE, and EMBASE from inception to June 2022, and hand searched clinical trial registries. We included randomized-controlled trials (RCTs) in adults, survivors of any type of cancer, that compared prehabilitation programs that had exercise training as the major component with usual care or other active interventions. Outcome measures were health-related quality of life (HRQL), muscular strength, postoperative complications, average length of stay (ALOS), handgrip strength, and physical activity levels. Two reviewers independently screened the studies, extracted data, and assessed the risk of bias and the certainty of the evidence.

RESULTS

Twenty-five RCTs (2682 participants) published between 2010 and 2022 met our inclusion criteria. Colorectal and lung cancers were the most common diagnoses. The studies had methodological concerns regarding outcome measurement, selective reporting, and attrition. Five prehabilitation programs were compared to usual care (rehabilitation): combined training, aerobic training, respiratory muscle training plus aerobic training, respiratory muscle training plus resistance training, and pelvic floor training. The studies provided no clear evidence of an effect between groups. We assessed the overall certainty of the evidence as very low, downgraded due to serious study limitations and imprecision.

CONCLUSION

Prehabilitation programs focusing on exercise training may have an effect on adults with cancer, but the evidence is very uncertain. We have very little confidence in the results and the true effect is likely to be substantially different from these. Further research is needed before we can draw a more certain conclusion.

SYSTEMATIC REVIEW REGISTRATION

CRD42019125658.

Citation of updated and co-published Cochrane Methodology Reviews

BACKGROUND

To evaluate the number of citations for Cochrane Methodology Reviews after they have been updated or co-published in another journal, and the effect of co-publishing the review on the co-publishing journal's impact factor (IF).

METHODS

We identified all Cochrane Methodology Reviews published in the Cochrane Database of Systematic Reviews (CDSR) before 2018 and searched for co-published versions in the Web of Science Core Collection database up to 16 August 2022. The included reviews were in two cohorts: those that had been published and updated in CDSR and those that had been published in CDSR and co-published in another journal. The primary outcome measured the citation number to updated and original reviews in the first five years after publication of the updated review, and assessed the citation number of co-published and non-co-published reviews in the first five years after publication of the co-published version. The secondary outcome was the ratio of an adjusted IF and the actual IF of the co-publishing journal.

RESULTS

Eight updated and six original reviews were identified for the updated cohort of reviews, and four co-published reviews were included in the co-published cohort. The original reviews continued to be cited after the update was published but the median for the total number of citations was non-significantly higher for the updated reviews than for their original version[161 (Interquartile range (IQR) 85, 198) versus 113 (IQR 15, 433)]. The median number of total citations [362 (IQR 179, 840) versus 145 (IQR 75, 445)] and the median number of citations to the review in the first five years after co-publication combined and in each of those years was higher in the co-published group than in the non-co-published group. One of the three journals that co-published Reviews in the first year and two journals in the second year had a lower IF after co-publication.

CONCLUSIONS

Earlier versions of Cochrane Methodology Reviews continue to be cited after an update is published, which raises doubts about whether those citing are using the most recent evidence or are aware of the update. Co-publication facilitates broader application and dissemination of Cochrane methodology evidence.

Use of appropriate statistical tools in biomedical research: Current trend & status

Background & objectives

Due to lack of appropriate statistical knowledge, published research articles contain various errors related to the design, analysis and interpretation of results in the area of biomedical research. If research contains statistical error, however, costly, it may be of no use and the purpose of the investigation gets defeated. Many biomedical research articles published in different peer reviewed journals may retain several statistical errors and flaws in them. This study aimed to examine the trend and status of application of statistics in biomedical research articles. Study design, sample size estimation and statistical measures are crucial components of a study. These points were evaluated in published original research articles to understand the use or misuse of statistical tools.

Methods

Three hundred original research articles from the latest issues of selected 37 journals were reviewed. These journals were from the five internationally recognized publication groups (CLINICAL KEY, BMJ Group, WILEY, CAMBRIDGE and OXFORD) accessible through the online library of SGPGI, Lucknow, India.

Results

Among articles assessed under present investigation, 85.3 per cent (n=256) were observational, and 14.7 per cent (n=44) were interventional studies. In 93 per cent (n=279) of research articles, sample size estimation was not reproducible. The simple random sampling was encountered rarely in biomedical studies even though none of the articles was adjusted by design effect and, only five articles had used randomized test. The testing of assumption of normality was mentioned in only four studies before applying parametric tests.

Interpretation & conclusions

In order to present biomedical research results with reliable and precise estimates based on data, the role of engaging statistical experts need to be appreciated. Journals must have standard rules for reporting study design, sample size and data analysis tools. Careful attention is needed while applying any statistical procedure as, it will not only help readers to trust in the published articles, but also rely on the inferences the published articles draw.

Psychotropic drugs for the treatment of non-suicidal self-injury in children and adolescents: a systematic review and meta-analysis

Non-suicidal self-injury (NSSI) in children and adolescents is a frequent phenomenon. NSSI at any time is a significant predictor of future NSSI but also, and more importantly, for suicide attempts. Less evidence is available for the impact, or more specifically, the therapeutic effect of psychotropic drugs on the emergence of NSSI in this population. The phenomenon is clinically highly relevant since adolescent psychiatric inpatients are often affected by NSSI and most of them are treated with psychotropic drugs. While previous reviews on NSSI comprised suicidal self-injury (SSI), this review aims at elucidating the potential impact of psychotropic drugs on the emergence of specifically NSSI in children and adolescents. Systematic searches of articles indexed electronically in PubMed, Embase and PsycInfo were conducted (PROSPERO CRD42020209505). Studies included in the quantitative synthesis were evaluated using the SIGN level of evidence rating. Meta-analyses were performed using RevMan (Version 5.4). 2227 records were identified through database searches. Two additional records were identified manually. In total, seven studies were included in qualitative and four studies in quantitative analyses. In a meta-analysis, selective serotonin reuptake inhibitors (SSRIs) were compared vs. control medication (placebo or serotonin-norepinephrine reuptake inhibitor) and here, no statistically significant difference between the groups could be observed regarding the frequency of NSSI events (Risk Ratio (RR) = 1.07, 95% confidence interval (CI) 0.60-1.91, p = 0.82, I² = 12%). Evidence regarding the association of SSRI use and NSSI among children and adolescents is sparse and the impact of psychotropic drugs in general on NSSI rates in this population should be addressed in future clinical and observational studies.

Benefits of Participation in Clinical Trials: An Umbrella Review

Participation in randomised clinical trials (RCTs) entails taking part in the discovery of effects of health care interventions. The question of whether participants' outcomes are different to those of non-participants remains controversial. This umbrella review was aimed at assessing whether there are health benefits of participation in RCTs, compared to non-participation. After prospective registration (PROSPERO CRD42021287812), we searched the Medline, Scopus, Web of Science and Cochrane Library databases from inception to June 2022 to identify relevant systematic reviews with or without meta-analyses. Data extraction and study quality assessment (AMSTAR-2) were performed by two independent reviewers. Of 914 records, six systematic reviews summarising 380 comparisons of RCT participants with non-participants met the inclusion criteria. In two reviews, the majority of comparisons were in favour of participation in RCTs. Of the total of comparisons, 69 (18.7%) were in favour of participation, reporting statistically significant better outcomes for patients treated within RCTs, 264 (71.7%) comparisons were not statistically significant, and 35 (9.5%) comparisons were in favour of non-participation. None of the reviews found a harmful effect of participation in RCTs. Our findings suggest that taking part in RCTs may be beneficial compared to non-participation.

Understanding the Interactions Between Driving Behavior and Well-being in Daily Driving: Causal Analysis of a Field Study

BACKGROUND

Investigating ways to improve well-being in everyday situations as a means of fostering mental health has gained substantial interest in recent years. For many people, the daily commute by car is a particularly straining situation of the day, and thus researchers have already designed various in-vehicle well-being interventions for a better commuting experience. Current research has validated such interventions but is limited to isolating effects in controlled experiments that are generally not representative of real-world driving conditions.

OBJECTIVE

The aim of the study is to identify cause-effect relationships between driving behavior and well-being in a real-world setting. This knowledge should contribute to a better understanding of when to trigger interventions.

METHODS

We conducted a field study in which we provided a demographically diverse sample of 10 commuters with a car for daily driving over a period of 4 months. Before and after each trip, the drivers had to fill out a questionnaire about their state of well-being, which was operationalized as arousal and valence. We equipped the cars with sensors that recorded driving behavior, such as sudden braking. We also captured trip-dependent factors, such as the length of the drive, and predetermined factors, such as the weather. We conducted a causal analysis based on a causal directed acyclic graph (DAG) to examine cause-effect relationships from the observational data and to isolate the causal chains between the examined variables. We did so by applying the backdoor criterion to the data-based graphical model. The hereby compiled adjustment set was used in a multiple regression to estimate the causal effects between the variables.

RESULTS

The causal analysis showed that a higher level of arousal before driving influences driving behavior. Higher arousal reduced the frequency of sudden events (P=.04) as well as the average speed (P=.001), while fostering active steering (P<.001). In turn, more frequent braking (P<.001) increased arousal after the drive, while a longer trip (P<.001) with a higher average speed (P<.001) reduced arousal. The prevalence of sunshine (P<.001) increased arousal and of occupants (P<.001) increased valence (P<.001) before and after driving.

CONCLUSIONS

The examination of cause-effect relationships unveiled significant interactions between well-being and driving. A low level of predriving arousal impairs driving behavior, which manifests itself in more frequent sudden events and less anticipatory driving. Driving has a stronger effect on arousal than on valence. In particular, monotonous driving situations at high speeds with low cognitive demand increase the risk of the driver becoming tired (low arousal), thus impairing driving behavior. By combining the identified causal chains, states of vulnerability can be inferred that may form the basis for timely delivered interventions to improve well-being while driving.

Perception of clinical research among patients and healthy volunteers of clinical trials

Purpose

Clinical research relies on data from patients and volunteers, yet the target sample size is often not achieved. Here, we assessed the perception of clinical research among clinical trial participants to improve the recruitment process for future studies.

Methods

We conducted a single-center descriptive and exploratory study of 300 current or former participants in various phase I–III clinical trials. Questionnaires were either distributed to current clinical trial participants or emailed to former subjects.

Results

Subjects strongly agreed or agreed that contributing to improving medical care (> 81%), contributing to scientific research (> 79%), and trusting their treating physicians (> 77%) were motives for study participation. Among healthy volunteers, financial motives positively correlated with the number of clinical trials they had participated in (p < 0.05). Higher age positively correlated with expectation of best available treatment during study participation among patients (p < 0.05). Less than 8% of all subjects expressed “great concern” about the potential risks of sharing their personal information as part of the study. Subjects displayed “great trust” or “trust” in medical staff (86.6%) and in government research institutions (76.4%), and “very little trust” or “little trust” in pharmaceutical companies (35.4%) and health insurance companies (16.9%).

Conclusion

Altruistic motives and trust in treating physicians were predominant motives for clinical trial participation. Older patients expected to receive the best available treatment during participation. Healthy volunteers who reported financial motives had participated in more clinical trials. Consistent with great trust in medical staff and government research institutions, little concern was expressed about the misuse of personal data during the trial.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00228-022-03366-3.

Internal Validity in Resistance Training Research: A Systematic Review

Ensuring internal validity is the key procedure when planning the study design. Numerous systematic reviews have demonstrated that considerations for internal validity do not receive adequate attention in the primary research in sport sciences. Therefore, the purpose of this study was to review methodological procedures in current literature where the effects of resistance training on strength, speed, and endurance performance in athletes were analyzed. A computer-based literature searches of SPORTDiscus, Scopus, Medline, and Web of Science was conducted. The internal validity of individual studies was assessed using the PEDro scale. Peer-reviewed studies were accepted only if they met all the following eligibility criteria: (a) healthy male and female athletes between the ages of 18-65 years; (b) training program based on resistance exercises; (c) training program lasted for at least 4 weeks or 12 training sessions, with at least two sessions per week; (d) the study reported maximum strength, speed, or endurance outcomes; and (e) systematic reviews, cohort studies, case-control studies, cross-sectional studies were excluded. Of the 6,516 articles identified, 133 studies were selected for rating by the PEDro scale. Sixty-eight percent of the included studies used random allocation to groups, but only one reported concealed allocation. Baseline data are presented in almost 69% of the studies. Thirty-eight percent of studies demonstrated adequate follow-up of participants. The plan to follow the intention-to-treat or stating that all participants received training intervention or control conditions as allocated were reported in only 1.5% of studies. The procedure of blinding of assessors was also satisfied in only 1.5% of the studies. The current study highlights the gaps in designing and reporting research in the field of strength and conditioning. Randomization, blinding of assessors, reporting of attrition, and intention-to-treat analysis should be more fully addressed to reduce threats to internal validity in primary research.

Examining trends in the evidence base for the treatment of burns and a quality assessment of randomised controlled trials over an 11-year period

BACKGROUND

Previous articles assessed the evidence-base for the treatment of burns, but the latest was published in 2010, examining data up to and inclusive of 2008. The aim of this article is to examine the trend in the number of high-evidence publications over the subsequent 11-year period and quality-assess RCTs within this timeframe.

MATERIALS AND METHODS

All articles published in Burns and Journal of Burn Care and Research (JBCR) were identified using PubMed Search Tools and its Single Citation Matcher function. These journals were manually screened from 01/01/2009-01/06/2020 inclusive. Additionally, a PubMed search was conducted searching for RCTs and meta-analyses in English with the MESH term burns to identify meta-analyses and RCTs in all other journals. The reporting of RCTs was assessed using a modified CONsolidated Standards of Reporting Trials (CONSORT) checklist.

RESULTS

A total of 5145 articles were evaluated from Burns and JBCR, with 3230 (62.78%) from Burns and 1915 (37.22%) from JBCR. 0.012% were meta-analyses of RCTs, 0.30% were other meta-analyses, and 2.52% were initially identified as RCTs. Whilst a significant increase in the number of high-evidence publications is observed, these represent 2.83% (n = 237) of the total. An additional 95 RCTs were identified in other journals, 58 being included in quality-analysis. A total 128 RCTs were thus eligible for quality-assessment, the most popular individual topic being wound healing (n = 28; 21.88%). The most highly reported criterion was listed inclusion and exclusion criteria (n = 111; 86.72%) and the least reported criterion was allocation concealment (n = 22; 13.92%).

CONCLUSIONS

This study observes a positive trend in high-evidence publications. The reporting of several CONSORT criteria in RCTs remains poor. Observation to standard reporting guidelines is advocated to improve the quality of reporting.

Effectiveness of Specific Neck Exercise for Nonspecific Neck Pain; Usefulness of Strategies for Patient Selection and Tailored Exercise-A Systematic Review With Meta-Analysis

OBJECTIVE

Specific neck exercises (SNE) targeting deep cervical flexors and extensors are commonly used for the treatment of nonspecific neck pain (NSNP). However, whether SNE are more effective than alternative exercise interventions (AEI) remains unclear. Furthermore, it has been postulated that SNE may be most effective when they are tailored and targeted to patients with evidence of motor control dysfunction, yet this notion also remains unproven. The objectives of this study were to compare the effectiveness of SNE with that of AEI for reducing pain and disability in people with NSNP and to assess whether the effectiveness of SNE is increased when the exercises are tailored and provided to patients with evidence of motor control dysfunction.

METHODS

For this systematic review with meta-analysis, Medline, Web of Science, Scopus, and Physiotherapy Evidence Database were searched. Eligibility criteria included randomized controlled trials evaluating the effectiveness of SNE against that of AEI in people with NSNP. Meta-analysis included subgroup analyses to determine the effect of exercise tailoring and participant selection criteria on the effectiveness of SNE.

RESULTS

Twelve studies were included. Meta-analysis revealed greater effectiveness of SNE in the short to medium term for reducing pain (pooled standardized mean difference [SMD] = -0.41; 95% CI = -0.76 to -0.06; P = .02) and disability (pooled SMD = -0.41; 95% CI = -0.78 to -0.04; P = .03) but no differences in the long term for pain (pooled SMD = -1.30; 95% CI = -3.35 to 0.75; P = .21) and disability (pooled SMD = -1.81; 95% CI = -4.29 to 0.67; P = .15), although evidence was limited for the latter. The effectiveness of SNE was not superior in studies that included only participants with motor control dysfunction or when exercises were tailored to each participant. Overall, the studies were of low quality. Grading of Recommendations Assessment, Development and Evaluation revealed low certainty, serious risk of bias, and inconsistency of findings for short- to medium-term effects and very low certainty, serious risk of bias, and very serious inconsistency for long-term effects.

CONCLUSION

The preferential use of SNE may be recommended to achieve better short- to medium-term outcomes, although the low quality of evidence affects the certainty of these findings. Currently used strategies for selecting patients and tailoring SNE are not supported by the evidence and therefore cannot be recommended for clinical practice.

IMPACT

SNE are more effective than AEI for reducing pain and disability in patients with NSNP in the short to medium term, but overall evidence is of low quality, affecting the certainty of the findings. Tests of muscle dysfunction (mostly the craniocervical flexion test) currently used in studies to select patients and tailor SNE do not result in greater effectiveness of these exercises.

LAY SUMMARY

Evidence suggests SNE are more effective than other forms of exercise, although evidence is overall of low quality. Use of the craniocervical flexion test in isolation to select participants and/or tailor SNE cannot be recommended.

Oral antiplatelet therapy for acute ischaemic stroke

BACKGROUND

In people with acute ischaemic stroke, platelets become activated and can cause blood clots to form and block an artery in the brain, resulting in damage to part of the brain. Such damage gives rise to the symptoms of stroke. Antiplatelet therapy might reduce the volume of brain damaged by ischaemia and also reduce the risk of early recurrent ischaemic stroke, thereby reducing the risk of early death and improving long-term outcomes in survivors. However, antiplatelet therapy might also increase the risk of fatal or disabling intracranial haemorrhage.

OBJECTIVES

To assess the efficacy and safety of immediate oral antiplatelet therapy (i.e. started as soon as possible and no later than two weeks after stroke onset) in people with acute presumed ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, and two trials registers, and performed forward reference/cited reference searching in August 2020.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing oral antiplatelet therapy (started within 14 days of the stroke) with control in people with definite or presumed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria and assessed trial quality. For the included trials, they extracted and cross-checked the data. They assessed risk of bias of each study using the Risk of Bias 1 (RoB1) tool and overall certainty of the evidence for each outcome using the GRADE approach.

MAIN RESULTS

We included 11 studies involving 42,226 participants. Three new trials have been added since the last update (743 participants). As per the previous version of this review, two trials testing aspirin 160 mg to 300 mg once daily, started within 48 hours of onset, contributed 96% of the data. The risk of bias was low. The maximum follow-up was six months. With treatment, there was a decrease in death or dependency at the end of follow-up (odds ratio (OR) 0.95, 95% confidence interval (CI) 0.91 to 0.99; 7 RCTs, 42,034 participants; moderate-certainty evidence). For every 1000 people treated with aspirin, 13 people would avoid death or dependency (number needed to treat for an additional beneficial outcome 79).

AUTHORS' CONCLUSIONS

Antiplatelet therapy with aspirin 160 mg to 300 mg daily, given orally (or by nasogastric tube or per rectum in people who cannot swallow) and started within 48 hours of onset of presumed ischaemic stroke, significantly decreased death and dependency, and reduced the risk of early recurrent ischaemic stroke without a major risk of early haemorrhagic complications; long-term outcomes were improved.

Considerations for clinical trial design and conduct in the evaluation of novel advanced therapeutics in neurodegenerative disease

The recent advances in the development of potentially disease modifying cell and gene therapies for neurodegenerative disease has resulted in the production of a number of promising novel therapies which are now moving forward to clinical evaluation. The robust evaluation of these therapies pose a significant number of challenges when compared to more traditional evaluations of pharmacotherapy, which is the current mainstay of neurodegenerative disease symptom management. Indeed, there is an inherent complexity in the design and conduct of these trials at multiple levels. Here we discuss specific aspects requiring consideration in the context of investigating novel cell and gene therapies for neurodegenerative disease. This extends to overarching trial designs that could be employed and the factors that underpin design choices such outcome assessments, participant selection and methods for delivery of cell and gene therapies. We explore methods of data collection that may improve efficiency in trials of cell and gene therapy to maximize data sharing and collaboration. Lastly, we explore some of the additional context beyond efficacy evaluations that should be considered to ensure implementation across relevant healthcare settings.

Effect of Antipsychotic Treatment on Neutrophil-to-Lymphocyte Ratio during Hospitalization for Acute Psychosis in the Course of Schizophrenia-A Cross-Sectional Retrospective Study

Background: Studies have shown that there are deviations in the results of peripheral blood counts, which lead to increased values of the neutrophils-to-lymphocytes ratio (NLR) in schizophrenia. Antipsychotic drugs have proven to lower the levels of pro-inflammatory cytokines and a growing number of studies indicate a similar effect on NLR values. Methods: We identified inpatients with schizophrenia and collected data of NLR at the beginning (NLR₁) and end (NLR₂) of hospitalization, the status of antipsychotic medication on admission and potential confounding factors. In the statistical analysis, we applied a linear mixed model. Results: After the inclusion and exclusion process the records of 40 patients (n_p = 40) and 71 hospitalizations (n_h = 71) were analyzed. We found that in the group of antipsychotics-naive patients, the NLR₁ were significantly higher than the NLR₂ values. Such a difference did not occur in the case of non-antipsychotics-naïve patients. Age and the diagnosis of hypothyroidism influenced the value of change in NLR from the beginning to the end of hospitalization in a given patient (ΔNLR). Conclusions: The study confirmed the lowering effect of antipsychotics on NLR values in psychosis. The NLR may potentially be a tool for assessing response to treatment with antipsychotics.

Anticoagulants for acute ischaemic stroke

BACKGROUND

Stroke is the third leading cause of early death worldwide. Most ischaemic strokes are caused by a blood clot blocking an artery in the brain. Patient outcomes might be improved if they are offered anticoagulants that reduce their risk of developing new blood clots and do not increase the risk of bleeding. This is an update of a Cochrane Review first published in 1995, with updates in 2004, 2008, and 2015.

OBJECTIVES

To assess the effectiveness and safety of early anticoagulation (within the first 14 days of onset) for people with acute presumed or confirmed ischaemic stroke. Our hypotheses were that, compared with a policy of avoiding their use, early anticoagulation would be associated with: • reduced risk of death or dependence in activities of daily living a few months after stroke onset; • reduced risk of early recurrent ischaemic stroke; • increased risk of symptomatic intracranial and extracranial haemorrhage; and • reduced risk of deep vein thrombosis and pulmonary embolism.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (August 2021); the Cochrane Database of Systematic Reviews (CDSR); the Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 7), in the Cochrane Library (searched 5 August 2021); MEDLINE (2014 to 5 August 2021); and Embase (2014 to 5 August 2021). In addition, we searched ongoing trials registries and reference lists of relevant papers. For previous versions of this review, we searched the register of the Antithrombotic Trialists' (ATT) Collaboration, consulted MedStrategy (1995), and contacted relevant drug companies.

SELECTION CRITERIA

Randomised trials comparing early anticoagulant therapy (started within two weeks of stroke onset) with control in people with acute presumed or confirmed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trial quality, and extracted data. We assessed the overall certainty of the evidence for each outcome using RoB1 and GRADE methods.

MAIN RESULTS

We included 28 trials involving 24,025 participants. Quality of the trials varied considerably. We considered some studies to be at unclear or high risk of selection, performance, detection, attrition, or reporting bias. Anticoagulants tested were standard unfractionated heparin, low-molecular-weight heparins, heparinoids, oral anticoagulants, and thrombin inhibitors. Over 90% of the evidence is related to effects of anticoagulant therapy initiated within the first 48 hours of onset. No evidence suggests that early anticoagulation reduced the odds of death or dependence at the end of follow-up (odds ratio (OR) 0.98, 95% confidence interval (CI) 0.92 to 1.03; 12 RCTs, 22,428 participants; high-certainty evidence). Similarly, we found no evidence suggesting that anticoagulant therapy started within the first 14 days of stroke onset reduced the odds of death from all causes (OR 0.99, 95% CI 0.90 to 1.09; 22 RCTs, 22,602 participants; low-certainty evidence) during the treatment period. Although early anticoagulant therapy was associated with fewer recurrent ischaemic strokes (OR 0.75, 95% CI 0.65 to 0.88; 12 RCTs, 21,665 participants; moderate-certainty evidence), it was also associated with an increase in symptomatic intracranial haemorrhage (OR 2.47; 95% CI 1.90 to 3.21; 20 RCTs, 23,221 participants; moderate-certainty evidence). Similarly, early anticoagulation reduced the frequency of symptomatic pulmonary emboli (OR 0.60, 95% CI 0.44 to 0.81; 14 RCTs, 22,544 participants; high-certainty evidence), but this benefit was offset by an increase in extracranial haemorrhage (OR 2.99, 95% CI 2.24 to 3.99; 18 RCTs, 22,255 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Since the last version of this review, four new relevant studies have been published, and conclusions remain consistent. People who have early anticoagulant therapy after acute ischaemic stroke do not demonstrate any net short- or long-term benefit. Treatment with anticoagulants reduced recurrent stroke, deep vein thrombosis, and pulmonary embolism but increased bleeding risk. Data do not support the routine use of any of the currently available anticoagulants for acute ischaemic stroke.

Are Most of the Published Clinical Trial Results in Restorative Dentistry Invalid? An Empirical Investigation

BACKGROUND

To establish the number of invalid clinical trial reports in restorative dentistry, due to lack of effective randomisation and/or inadequate sample size and whether this number changed, during the 1990-2019 period.

METHODS

Databases were searched up to 14 July 2019 without limitations regarding publication language. A Journal hand search and reference check were conducted for trial reports. Selection criteria were: reporting on a prospective, controlled clinical trial; relevance to placing direct tooth restorations in human vital teeth; direct comparison between restorative materials concerning tooth restoration longevity; trial report published from 1990. Randomisation reported (Yes/No) and treatment group sample size ≥ 200 were applied as criteria, using the deductive falsification approach for trial report appraisal.

RESULTS

683 trial reports were appraised. 660 lacked effective randomisation. Of the remaining 23 reports, only 2 included a sample size of more than 200 restored teeth (mean number per treatment group 87; Standard deviation = 108.51). 92.5% of all treatment groups had a sample size of < 200. Randomisation reporting increased and sample size remained essentially unchanged between 1990 and 2019.

CONCLUSION

Most of the published clinical trial results in restorative dentistry were judged invalid, due to lack of effective randomisation and adequate sample size. These results are in line with previous findings. Evidence-based recommendations on how to improve trial methodology are available in the dental/medical literature.

Views of healthcare professionals on recruiting to a psychosocial randomised controlled trial: a qualitative study

BACKGROUND

Randomised controlled trials, and in particular those of psychosocial interventions, often fail to recruit to target, resulting in underpowered trials with poor generalisability of findings. The objectives of this study were to explore the views of healthcare professionals on recruiting to psychosocial research studies, and to explore their views on factors that may hinder or facilitate recruitment.

METHODS

We conducted 14 semi-structured interviews, with healthcare professionals who had been involved in recruitment into a randomised controlled trial of a talking therapy for depression in patients with advanced cancer. Interviews were transcribed and analysed using thematic analysis.

RESULTS

Five primary themes were identified, comprised of 11 subthemes. Attitudes towards research were largely positive. Health care professionals identified lack of time and narrow screening criteria as barriers to recruitment, and also noted the tendency to withhold participants from research for reasons other than eligibility (e.g., gatekeeping). The engagement of the study team with the clinical recruitment site, and the frequent presence of a researcher in clinics, were noted as facilitating recruitment.

CONCLUSIONS

Healthcare professionals involved in recruiting to trials of psychosocial interventions hold generally positive views of psychosocial research. However, they report that constraints including space and time limit their ability to recruit, and express anxieties about approaching patients for trial recruitment in the palliative phase of their illness. The findings from this study can inform how best to design trials, and in particular trials of psychosocial interventions, and train health care professionals for the study, to maximise recruitment.

The Composite Quality Score (CQS) as a trial appraisal tool: inter-rater reliability and rating time

OBJECTIVE

To establish the CQS inter-rater reliability and rating time and to compare both against that of the Jadad scale and Cochrane's Risk of Bias Tool (ROBT).

MATERIAL AND METHODS

Four independent raters rated 45 trial reports. The inter-rater reliability was established by use of the Brennan-Prediger coefficient (BPC). The coefficients were compared using the two-sample z-test. Secondary analysis included comparison of the inter-rater reliability of the randomization component of all tools, as well as of the allocation concealment component of the CQS to that of the ROBT. The mean rating time with standard deviation (SD) for each tool was determined using one-way repeated measures analysis of variance. Post hoc comparisons were made using the Tukey-Kramer adjustment for three pair-wise multiple comparisons.

RESULTS

The inter-rater reliability was significantly higher for the CQS (BPC, 95% CI: 0.95, 0.87-1.00) compared to Jadad (0.70, 0.58-0.82) (adjusted p = 0.0005) and most components of ROBT. The mean (SD) time to complete the CQS (4.0 (1.0) min) did not differ significantly from that of the Jadad scale 4.8 (1.1) min (adjusted p = 0.11), but was significantly shorter compared to that of the ROBT 15.3 (5.9) min (adjusted p < 0.0001).

CONCLUSIONS

The results suggest the CQS to be a very reliable and fast trial appraisal tool. Clinical relevance The higher the inter-rater reliability, the higher the probability that trial results reflect therapeutic truth. The CQS will need to take further bias sources into consideration, in order to increase its utility.

Research design considerations for randomized controlled trials of spinal cord stimulation for pain: Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials/Institute of Neuromodulation/International Neuromodulation Society recommendations

ABSTRACT

Spinal cord stimulation (SCS) is an interventional nonpharmacologic treatment used for chronic pain and other indications. Methods for evaluating the safety and efficacy of SCS have evolved from uncontrolled and retrospective studies to prospective randomized controlled trials (RCTs). Although randomization overcomes certain types of bias, additional challenges to the validity of RCTs of SCS include blinding, choice of control groups, nonspecific effects of treatment variables (eg, paresthesia, device programming and recharging, psychological support, and rehabilitative techniques), and safety considerations. To address these challenges, 3 professional societies (Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials, Institute of Neuromodulation, and International Neuromodulation Society) convened a meeting to develop consensus recommendations on the design, conduct, analysis, and interpretation of RCTs of SCS for chronic pain. This article summarizes the results of this meeting. Highlights of our recommendations include disclosing all funding source and potential conflicts; incorporating mechanistic objectives when possible; avoiding noninferiority designs without internal demonstration of assay sensitivity; achieving and documenting double-blinding whenever possible; documenting investigator and site experience; keeping all information provided to patients balanced with respect to expectation of benefit; disclosing all information provided to patients, including verbal scripts; using placebo/sham controls when possible; capturing a complete set of outcome assessments; accounting for ancillary pharmacologic and nonpharmacologic treatments in a clear manner; providing a complete description of intended and actual programming interactions; making a prospective ascertainment of SCS-specific safety outcomes; training patients and researchers on appropriate expectations, outcome assessments, and other key aspects of study performance; and providing transparent and complete reporting of results according to applicable reporting guidelines.

Clinical signs of possible serious infection and associated mortality among young infants presenting at first-level health facilities

BACKGROUND

The World Health Organization recommends inpatient hospital treatment of young infants up to two months old with any sign of possible serious infection. However, each sign may have a different risk of death. The current study aims to calculate the case fatality ratio for infants with individual or combined signs of possible serious infection, stratified by inpatient or outpatient treatment.

METHODS

We analysed data from the African Neonatal Sepsis Trial conducted in five sites in the Democratic Republic of the Congo, Kenya and Nigeria. Trained study nurses classified sick infants as pneumonia (fast breathing in 7-59 days old), severe pneumonia (fast breathing in 0-6 days old), clinical severe infection [severe chest indrawing, high (> = 38°C) or low body temperature (<35.5°C), stopped feeding well, or movement only when stimulated] or critical illness (convulsions, not able to feed at all, or no movement at all), and referred them to a hospital for inpatient treatment. Infants whose caregivers refused referral received outpatient treatment. The case fatality ratio by day 15 was calculated for individual and combined clinical signs and stratified by place of treatment. An infant with signs of clinical severe infection or severe pneumonia was recategorised as having low- (case fatality ratio ≤2%) or moderate- (case fatality ratio >2%) mortality risk.

RESULTS

Of 7129 young infants with a possible serious infection, fast breathing (in 7-59 days old) was the most prevalent sign (26%), followed by high body temperature (20%) and severe chest indrawing (19%). Infants with pneumonia had the lowest case fatality ratio (0.2%), followed by severe pneumonia (2.0%), clinical severe infection (2.3%) and critical illness (16.9%). Infants with clinical severe infection had a wide range of case fatality ratios for individual signs (from 0.8% to 11.0%). Infants with pneumonia had similar case fatality ratio for outpatient and inpatient treatment (0.2% vs. 0.3%, p = 0.74). Infants with clinical severe infection or severe pneumonia had a lower case fatality ratio among those who received outpatient treatment compared to inpatient treatment (1.9% vs. 6.5%, p<0.0001). We recategorised infants into low-mortality risk signs (case fatality ratio ≤2%) of clinical severe infection (high body temperature, or severe chest indrawing) or severe pneumonia and moderate-mortality risk signs (case fatality ratio >2%) (stopped feeding well, movement only when stimulated, low body temperature or multiple signs of clinical severe infection). We found that both categories had four times lower case fatality ratio when treated as outpatient than inpatient treatment, i.e., 1.0% vs. 4.0% (p<0.0001) and 5.3% vs. 22.4% (p<0.0001), respectively. In contrast, infants with signs of critical illness had nearly two times higher case fatality ratio when treated as outpatient versus inpatient treatment (21.7% vs. 12.1%, p = 0.097).

CONCLUSIONS

The mortality risk differs with clinical signs. Young infants with a possible serious infection can be grouped into those with low-mortality risk signs (high body temperature, or severe chest indrawing or severe pneumonia); moderate-mortality risk signs (stopped feeding well, movement only when stimulated, low body temperature or multiple signs of clinical severe infection), or high-mortality risk signs (signs of critical illness). New treatment strategies that consider differential mortality risks for the place of treatment and duration of inpatient treatment could be developed and evaluated based on these findings.

CLINICAL TRIAL REGISTRATION

This trial was registered with the Australian New Zealand Clinical Trials Registry under ID ACTRN 12610000286044.

Modelling hospital outcome: problems with endogeneity

Background

Mortality modelling in the critical care paradigm traditionally uses logistic regression, despite the availability of estimators commonly used in alternate disciplines. Little attention has been paid to covariate endogeneity and the status of non-randomized treatment assignment. Using a large registry database, various binary outcome modelling strategies and methods to account for covariate endogeneity were explored.

Methods

Patient mortality data was sourced from the Australian & New Zealand Intensive Society Adult Patient Database for 2016. Hospital mortality was modelled using logistic, probit and linear probability (LPM) models with intensive care (ICU) providers as fixed (FE) and random (RE) effects. Model comparison entailed indices of discrimination and calibration, information criteria (AIC and BIC) and binned residual analysis. Suspect covariate and ventilation treatment assignment endogeneity was identified by correlation between predictor variable and hospital mortality error terms, using the Stata™ “eprobit” estimator. Marginal effects were used to demonstrate effect estimate differences between probit and “eprobit” models.

Results

The cohort comprised 92,693 patients from 124 intensive care units (ICU) in calendar year 2016. Patients mean age was 61.8 (SD 17.5) years, 41.6% were female and APACHE III severity of illness score 54.5(25.6); 43.7% were ventilated. Of the models considered in predicting hospital mortality, logistic regression (with or without ICU FE) and RE logistic regression dominated, more so the latter using information criteria indices. The LPM suffered from many predictions outside the unit [0,1] interval and both poor discrimination and calibration. Error terms of hospital length of stay, an independent risk of death score and ventilation status were correlated with the mortality error term. Marked differences in the ventilation mortality marginal effect was demonstrated between the probit and the "eprobit" models which were scenario dependent. Endogeneity was not demonstrated for the APACHE III score.

Conclusions

Logistic regression accounting for provider effects was the preferred estimator for hospital mortality modelling. Endogeneity of covariates and treatment variables may be identified using appropriate modelling, but failure to do so yields problematic effect estimates.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01251-8.

Recruiting hard-to-reach pregnant women at high psychosocial risk: strategies and costs from a randomised controlled trial

BACKGROUND

Recruiting participants to randomised controlled trials (RCTs) is often challenging, particularly when working with socially disadvantaged populations who are often termed 'hard-to-reach' in research. Here we report the recruitment strategies and costs for the Trial for Healthy Relationship Initiatives in the Very Early years (THRIVE), an RCT evaluating two group-based parenting interventions for pregnant women.

METHODS

THRIVE aimed to recruit 500 pregnant women with additional health and social care needs in Scotland between 2014 and 2018. Three recruitment strategies were employed: (1) referrals from a health or social care practitioner or voluntary/community organisation (practitioner-led referral), (2) direct engagement with potential participants by research staff (researcher-led recruitment) and (3) self-referral in response to study advertising (self-referral). The number of referrals and recruited participants from each strategy is reported along with the overall cost of recruitment. The impact of recruitment activities and the changes in maternity policy/context on recruitment throughout the study are examined.

RESULTS

THRIVE received 973 referrals: 684 (70%) from practitioners (mainly specialist and general midwives), 273 (28%) from research nurses and 16 (2%) self-referrals. The time spent in antenatal clinics by research nurses each month was positively correlated with the number of referrals received (r = 0.57; p < 0.001). Changes in maternity policies and contexts were reflected in the number of referrals received each month, with both positive and negative impacts throughout the trial. Overall, 50% of referred women were recruited to the trial. Women referred via self-referral, THRIVE research nurses and specialist midwives were most likely to go on to be recruited (81%, 58% and 57%, respectively). Key contributors to recruitment included engaging key groups of referrers, establishing a large flexible workforce to enable recruitment activities to adapt to changes in context throughout the study and identifying the most appropriate setting to engage with potential participants. The overall cost of recruitment was £377 per randomised participant.

CONCLUSIONS

Recruitment resulted from a combination of all three strategies. Our reflections on the successes and challenges of these strategies highlight the need for recruitment strategies to be flexible to adapt to complex interventions and real-world challenges. These findings will inform future research in similar hard-to-reach populations.

TRIAL REGISTRATION

International Standard Randomised Controlled Trials Number Registry ISRCTN21656568 . Retrospectively registered on 28 February 2014.

Bias estimation in study design: a meta-epidemiological analysis of transcatheter versus surgical aortic valve replacement

BACKGROUND

Paucity of RCTs of non-drug technologies lead to widespread dependence on non-randomized studies. Relationship between nonrandomized study design attributes and biased estimates of treatment effects are poorly understood. Our purpose was to estimate the bias associated with specific nonrandomized study attributes among studies comparing transcatheter aortic valve implantation with surgical aortic valve replacement for the treatment of severe aortic stenosis.

RESULTS

We included 6 RCTs and 87 nonrandomized studies. Surgical risk scores were similar for comparison groups in RCTs, but were higher for patients having transcatheter aortic valve implantation in nonrandomized studies. Nonrandomized studies underestimated the benefit of transcatheter aortic valve implantation compared with RCTs. For example, nonrandomized studies without adjustment estimated a higher risk of postoperative mortality for transcatheter aortic valve implantation compared with surgical aortic valve replacement (OR 1.43 [95% CI 1.26 to 1.62]) than high quality RCTs (OR 0.78 [95% CI 0.54 to 1.11). Nonrandomized studies using propensity score matching (OR 1.13 [95% CI 0.85 to 1.52]) and regression modelling (OR 0.68 [95% CI 0.57 to 0.81]) to adjust results estimated treatment effects closer to high quality RCTs. Nonrandomized studies describing losses to follow-up estimated treatment effects that were significantly closer to high quality RCT than nonrandomized studies that did not.

CONCLUSION

Studies with different attributes produce different estimates of treatment effects. Study design attributes related to the completeness of follow-up may explain biased treatment estimates in nonrandomized studies, as in the case of aortic valve replacement where high-risk patients were preferentially selected for the newer (transcatheter) procedure.

Evaluation of the Quality of Perinatal Trials: Making the GRADE

BACKGROUND

Assessing the quality of clinical research is a key evidence-based practice skill. Clinicians, guideline producers, policy makers, service commissioners, and families need to have a sense of the validity, applicability, and certainty of research evidence when determining how it should inform their decision-making and practice.

METHODS

We consider the various methodological and study design factors that contribute to the validity and applicability of clinical research findings. We describe the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) methodology and discuss how this approach is used to assess and report certainty of evidence and strength of recommendations.

RESULTS

The randomized controlled trial (RCT) is the gold standard method for assessing interventions because randomization balances prognostic characteristics between comparison groups. The GRADE approach considers evidence from RCTs as high quality, but acknowledges that the quality and level of certainty of trial evidence may be "downgraded" based on consideration of threats across 5 domains: risk of bias in included trials, inconsistency between trials in outcome estimates, indirectness of the evidence, imprecision of estimates, and likelihood of publication bias.

CONCLUSIONS

Structured critical appraisal using GRADE methods to assess risk of bias and other threats to the internal and external validity of RCTs and systematic reviews and meta-analyses of their data facilitates transparency and consistency in using evidence to inform policy and practice.

Effect of a 6-Month Controlled Lifestyle Intervention on Common Carotid Intima-Media Thickness

OBJECTIVES

The intima-media thickness of the common carotid artery (ccIMT) is an established risk marker for cardiovascular disease (CVD). However, it is unclear whether lifestyle interventions can easily demonstrate an improvement in ccIMT. The objective was to test if our intervention would beneficially affect ccIMT (among other CVD markers).

DESIGN

Non-randomized controlled trial.

SETTING

Rural northwest Germany.

PARTICIPANTS

Middle-aged and elderly participants from the general population (intervention: n = 114; control: n = 87).

INTERVENTION

A community-based, 6-month controlled lifestyle intervention focusing on four areas of lifestyle change: a plant-based diet, physical activity, stress management, and an improved social life. A strong emphasis was on dietary change.

MEASUREMENTS

We tested whether ccIMT change from baseline to 6 months was different between groups.

RESULTS

With all participants included, no significant difference in mean ccIMT change between groups was observed (p = 0.708). However, in a subgroup analysis with participants with high baseline mean ccIMT (≥0.800 mm) a significant difference in mean ccIMT change between intervention (-0.023 [95% CI -0.052, 0.007] mm; n = 22; baseline mean ccIMT: 0.884 ± 0.015 mm) and control (0.041 [95% CI 0.009, 0.073] mm; n = 13; baseline mean ccIMT: 0.881 ± 0.022 mm) was observed (p = 0.004). Adjusting for potential confounders did not substantially alter the results.

CONCLUSION

The results indicate that healthy lifestyle changes can beneficially affect ccIMT within 6 months and that such a beneficial effect may be more easily demonstrated if participants with high baseline ccIMT are recruited. The observed effect is of relevance for the prevention of CVD events, including myocardial infarction and stroke.

Bayesian Statistics for Surgical Decision Making

Background: Application of clinical study findings to surgical decision making requires accurate interpretation of the results, integration of the findings within the context of pre-existing knowledge and use of statistics to answer clinically relevant questions. Bayesian analyses are optimally suited for interpretation of study findings, supporting translation to the bedside. Discussion: Surgical decision making is a complex process that draws on an individual clinician's medical knowledge, experience, data, and the patient's unique characteristics and preferences. Subjective and objective knowledge may be merged to derive a probability of benefit or harm of a treatment under consideration. Bayesian reasoning complements the clinical decision-making process by incorporating known evidence and data from a new study to determine the probability of an outcome of interest. Bayesian analyses are statistically robust and intuitive when translating findings of a study into clinical care. In contrast, frequentist statistics are poorly suited to translate study findings to clinical application. This review aims to highlight the benefits of incorporating Bayesian analyses into clinical research. Conclusion: Bayesian analyses offer clinically relevant information including the probability of benefit or harm of a treatment under consideration while accounting for uncertainty. This information may be incorporated easily and accurately into surgical decision making.

Design and conduct of confirmatory chronic pain clinical trials

The purpose of this article is to provide readers with a basis for understanding the emerging science of clinical trials and to provide a set of practical, evidence-based suggestions for designing and executing confirmatory clinical trials in a manner that minimizes measurement error. The most important step in creating a mindset of quality clinical research is to abandon the antiquated concept that clinical trials are a method for capturing data from clinical practice and shifting to a concept of the clinical trial as a measurement system, consisting of an interconnected set of processes, each of which must be in calibration for the trial to generate an accurate and reliable estimate of the efficacy (and safety) of a given treatment. The status quo of inaccurate, unreliable, and protracted clinical trials is unacceptable and unsustainable. This article gathers aspects of study design and conduct under a single broad umbrella of techniques available to improve the accuracy and reliability of confirmatory clinical trials across traditional domain boundaries.

Low-Frequency Repetitive Transcranial Magnetic Stimulation in Patients With Poststroke Aphasia: Systematic Review and Meta-Analysis of Its Effect Upon Communication

Objective The aim of the study was to investigate the effectiveness and safety of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) in patients with poststroke aphasia. Method We comprehensively searched for eligible studies from 11 electronic medical databases from their inception to February 20, 2019. Randomized controlled trials reporting the effectiveness of LF-rTMS for patients with poststroke aphasia were included. The primary outcome was language ability. The secondary outcomes were functional communication and adverse events. The methodological quality of the randomized controlled trials was evaluated by the Cochrane Back Review Group Risk of Bias Assessment Criteria. Results Of the 567 records retrieved, 18 studies with a total of 536 participants were included. All the included studies were of relatively acceptable methodological quality. All studies but one used LF-rTMS + speech and language therapy (SLT), not LF-rTMS alone. The meta-analysis showed that LF-rTMS had beneficial effects for patients with aphasia after a stroke in terms of naming, repetition, comprehension, written language, and functional communication. The subgroup analyses of language performance showed positive effects of LF-rTMS among stroke patients with chronic aphasia and acute aphasia. LF-rTMS + SLT had effects on language performance that were superior to the sham rTMS + SLT and SLT alone. A shorter LF-rTMS duration benefited language performance more than a longer duration. Additionally, 20 min of LF-rTMS per session produced a positive effect on language ability for patients with aphasia after a stroke. No adverse events were reported. Conclusions LF-rTMS + SLT is an effective and safe method for patients with poststroke aphasia to improve their language performance. Additionally, the most commonly used LF-rTMS protocol for patients with aphasia after a stroke was 90% of the resting motor threshold 20 min per day, 5 days per week, for 2 weeks.

Effectiveness of Whitening Strips Use Compared With Supervised Dental Bleaching: A Systematic Review and Meta-analysis

CLINICAL RELEVANCE

Bleaching performed at home while under the supervision of a dentist provides greater color alteration compared with whitening strips when evaluated with a spectrophotometer, although the color alteration was undetectable by unaided human eyes.

SUMMARY

Objective: A systematic review and meta-analysis were performed to answer the following research question: Does the use of whitening strips (WS) lead to an equivalent color change compared with supervised dental bleaching in patients with permanent dentition?Methods: A search was performed on August 10, 2017 (updated on March 22, 2019), in PubMed, the Brazilian Library in Dentistry, Latin American and Caribbean Health Sciences Literature database, Cochrane Library, Scopus, Web of Science, and SIGLE, without restrictions regarding date or language. Abstracts from the International Association for Dental Research, unpublished and ongoing trial registries, dissertations, and theses were also searched. Only randomized clinical trials (parallel or split mouth) in patients with permanent dentition that compared WS with dentist-supervised dental bleaching performed at home (AH) or in office (IO) were included. The risk of bias (RoB) was evaluated using the Cochrane Collaboration tool. A meta-analysis with subgroup analysis (low and high peroxide concentration) was conducted for color change ΔE* (spectrophotometer) and ΔSGU (shade guide units), risk and intensity of tooth sensitivity (TS), gingival irritation (GI), and patient satisfaction using a random effects model. Heterogeneity was assessed with the Cochrane Q test and I2 statistics. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) was used to assess the quality of the evidence.Results: After the removal of duplicates, followed by title and abstract screening, 20 studies remained. Only two studies were considered to have a low RoB; 11 had a high RoB, and seven had an unclear RoB. For WS versus IO, data were not available for the meta-analysis. For WS versus AH bleaching, a significant difference in ΔE* favoring the AH group was observed (standardized mean difference [SMD] = -0.50, 95% confidence interval [CI] -0.79 to 0.21), but the risk (risk ratio = 0.78, 95% CI 0.65 to 0.93) and intensity of TS (SMD = -0.30, 95% CI -0.56 to -0.04) were lower in the WS group. Color change in ΔSGU, risk and intensity of GI, and patient satisfaction were not significantly different between groups (p>0.20). The quality of evidence for ΔE*, risk and intensity of TS, and intensity of GI were graded as moderate.Conclusion: Although the risk and intensity of TS were lower in the WS group, dentist-supervised at-home bleaching led to a better color change when measured with a spectrophotometer, although the color alteration was undetectable by unaided human eyes.

Pharmacist and patient perspectives on recruitment strategies for randomized controlled trials: a qualitative analysis

BACKGROUND

Although recruitment is a major challenge for most randomized controlled trials, few report on the difficulties of recruitment, or how it might be enhanced. The objective of our study was to qualitatively explore the experiences of both patients and pharmacists related to recruitment for ACCESS, a large trial involving low-income seniors, given that two of our most successful recruitment strategies were direct patient recruitment materials and use of community pharmacists.

METHODS

Using qualitative descriptive methods, we collected data from pharmacists and study participants. Pharmacists were asked about their impressions of the study, as well as challenges they faced and methods they used to recruit potential participants. Focus groups with trial participants centered on the patient recruitment materials. Interviews and focus groups were recorded, transcribed and analyzed using thematic analysis.

RESULTS

Pharmacists noted that their first impressions of the study were positive as they described being enticed to help the study team by the potential benefit of copayment elimination for their patients and the low time commitment. Pharmacists noted they were more likely to recruit if they were well informed on the study, as they could answer their patients' questions. Participants noted that their primary motivations for participating were the tangible benefits of free medications and the intrinsic value of participating in research.

CONCLUSIONS

We noted that recruitment through pharmacies was an effective method as most patients have trusting relationships with their pharmacist. To optimize recruitment through pharmacies, study procedures should be straightforward, and pharmacists need to be equipped with good knowledge of the study. When promoting a study to potential participants, messaging should ensure the individuals are aware of the tangible benefits of participation while still presenting a full overview of the trial.

TRIAL REGISTRATION

Trial Registration Number: NCT02579655 - initially registered Oct 19, 2015.

Perinatal epidemiology: Issues, challenges, and potential solutions

Perinatal epidemiology research is concerned with identifying the effects of events during pregnancy on pregnancy outcomes that include maternal, fetal, and neonatal health outcomes. Randomized trials in perinatal research face many challenges, including randomization difficulties, ethical considerations, and inadequate statistical power due to the small number of subjects eligible for participation. For these reasons, most epidemiological studies conducted in this research field are observational and include different types of bias. This review describes the key methodological difficulties in the design and analysis of randomized and observational studies in perinatal epidemiology, and provides potential corrective approaches.

The WELL diet score correlates with the alternative healthy eating index-2010

The quality of one's overall diet has proven to be of great importance to health and well-being. Unfortunately, diet quality is time-consuming to assess. The Stanford Wellness Living Laboratory (WELL) administered an online survey that included the WELL Diet Score (a novel diet quality assessment calculated from 12 diet-related items). Subsequently, WELL participants were asked to complete the 127-item Block Food Frequency Questionnaire (FFQ) online. The present study's primary objective was to compare the WELL Diet Score with the established FFQ-based Alternative Healthy Eating Index-2010 (AHEI-2010), in a subset of WELL participants (n = 248) who completed both dietary measures through WELL's online platform. The two scores were significantly correlated (r = .69; p < .0001). Regression analyses demonstrated that the WELL Diet Score was positively significantly associated with sociodemographic determinants of diet quality and protective health factors, including older age, higher education, lower BMI, and higher physical activity. In summary, the WELL Diet Score, derived from 12 small diet-related items that can be completed in 5 min, was significantly positively correlated with the AHEI-2010 derived from the lengthy 127-item FFQ, suggesting the potential utility of the WELL Diet Score in future large-scale studies, including future WELL studies.

A systematic review of non-randomised evaluations of strategies to improve participant recruitment to randomised controlled trials

Background: Recruitment to trials can be challenging. Currently, non-randomised evaluations of trial recruitment interventions are rejected due to poor methodological quality, but systematic assessment of this substantial body of work may inform trialists’ decision-making about recruitment methods. Our objective was to quantify the effects of strategies to improve participant recruitment to randomised trials evaluated using non-randomised study designs.

Methods: We searched relevant databases for non-randomised studies that included two or more interventions evaluating recruitment to trials. Two reviewers screened abstracts and full texts for eligible studies, then extracted data on: recruitment intervention, setting, participant characteristics, number of participants in intervention and comparator groups. The ROBINS-I tool was used to assess risk of bias. The primary outcome was the number of recruits to a trial.

Results: We identified 92 studies for inclusion; 90 studies aimed to improve the recruitment of participants, one aimed to improve the recruitment of GP practices, and one aimed to improve recruitment of GPs. Of the 92 included studies, 20 were at high risk of bias due to confounding; the remaining 72 were at high risk of bias due to confounding and at least one other category of the ROBINS-I tool. The 20 studies at least risk of bias were synthesised narratively based on seven broad categories; Face to face recruitment initiatives, postal invitations and responses, language adaptations, randomisation methods, trial awareness strategies aimed at the recruitee, trial awareness strategies aimed at the recruiter, and use of networks and databases. The utility of included studies is substantially limited due to small sample sizes, inadequate reporting, and a lack of coordination around deciding what to evaluate and how.

Conclusions: Careful thought around planning, conduct, and reporting of non-randomised evaluations of recruitment interventions is required to prevent future non-randomised studies contributing to research waste.

Registration: PROSPERO CRD42016037718

Randomised Controlled Trials for Informing Perinatal Care

BACKGROUND

Randomised controlled trials provide the best evidence for the effects of interventions and are a key tool in the effort to improve the care and outcomes for newborn infants.

METHODS

We discuss the role of randomisation for minimising selection bias in clinical trials and describe examples of seminal trials that have shaped the development of modern perinatal care. We consider the challenges inherent in designing and delivering large, simple, and pragmatic trials, and the need for the development and adoption of core outcome sets to ensure that trials provide high-quality evidence of sufficient validity and applicability to guide policy and practice.

RESULTS

Since the earliest days of modern neonatology, the randomised controlled trial has been recognised as the best method for assessing treatments and practices. While many strategies that reduce mortality and morbidity have been introduced following randomised trials, there are, however, important examples of ineffective or potentially harmful practices that have been adopted in the absence of trial-based evidence. Typically, randomised controlled trials in perinatal care need to recruit several thousand participants to be able to detect modest but potentially important effects of new interventions on the most important but rare outcomes. Given the concerns about the financial burden and regulatory complexity of standard trial designs, innovative "efficient" trial designs are being evaluated to streamline processes while safeguarding participants.

CONCLUSIONS

Well-conducted randomised controlled trials provide the most robust evaluation of interventions aimed at improving outcomes for newborn infants and their families. Increasingly, these trials will need to be large and multicentre (often international) and use a simple and pragmatic protocol, incorporating meticulous follow-up procedures and assessment of long-term outcomes.

Using Forbidden Points in Pregnancy: Adverse Outcomes and Quality of Evidence in Randomized Controlled Trials-A Systematic Narrative Review

Objective: Pregnancy is a complex physical and hormonal condition. Many women experience back and pelvic pain, reflux, and headaches during pregnancy. There has been a significant rise in the popularity of acupuncture for pain conditions in pregnancy, wherein nonpharmacologic options are important. Concerns have been raised by both traditional and medical acupuncturists about using "forbidden points" during pregnancy and the risk of preterm contractions (PTC), as this could limit women's and practitioners' willingness to continue treatment during pregnancy. There is also a risk of bias introduced into clinical trials when participants are highly selected or they drop out of studies due to adverse outcomes. This review examined randomized controlled trials (RCTs) of acupuncture using forbidden points prior to 37 weeks of pregnancy to treat pain conditions, with the primary outcome of PTC. Methods: A database search identified RCTs, including trials of penetrating acupuncture that used forbidden points in their protocols to treat pregnancy-related pain conditions. STRICTA [Standards for Reporting Interventions in Clinical Trials of Acupuncture] and GRADE [Grades of Recommendation, Assessment, Development, and Evaluation] criteria were used to assess the quality of evidence. This review includes 8 RCTs reporting on 713 women. Results: Only 2 studies reported on the primary outcome of PTC, and there were insufficient data to perform a primary analysis. In these 2 studies, 6 participants withdrew due to PTC. No study was at a low risk of bias for all GRADE domains, and 3 studies were at high or unclear risk of bias in all domains. Conclusions: PTC is an important clinical outcome and should be reported routinely. The strength of evidence to date is insufficient to recommend using forbidden points prior to 37 weeks of pregnancy. Highly selected patient populations, risk of bias in study design, and participant withdrawal rates, suggest that high-quality trials are required.

Tasuki for neck pain: An individually-randomized, open-label, waiting-list-controlled trial

OBJECTIVES

Neck pain ranks 4th highest in terms of disability as measured by years lived with disabilities. This study was conducted to determine whether Tasuki-style posture supporter improves neck pain compared to waiting-list.

METHODS

This trial was an individually-randomized, open-label, waiting-list-controlled study. Adults (20 years or older) with non-specific chronic neck pain who reported 10 points or more on modified Neck Disability Index (mNDI: range, 0-50; higher points indicate worse condition) were enrolled. Participants were randomly assigned 1:1 to the intervention group or waiting-list. Prespecified primary outcome was the change in mNDI at 1 week. The principle of intention-to-treat analyses (as randomized) was applied. This trial was prospectively registered with UMIN (UMIN000034825).

RESULTS

In total, 50 participants (mean age, 40.9 [standard deviation (SD) = 9.6]; 32 participants [64%] were female, mean mNDI, 14.3 [SD = 2.9]) were enrolled. Of these participants, 26 (52%) were randomly assigned to the intervention group and 24 (48%) to the waiting-list. Attrition rate was low in both groups (1/50). The mean mNDI change score at 1 week was more favorable for Tasuki than waiting-list (between-group difference, -3.5 points (95% confidence interval (CI), -5.3 to -1.8); P = .0002). More participants (58%) had moderate benefit (at least 30% improvement) with Tasuki than waiting-list (13%) (relative risk 4.6 (95% CI 1.5 to 14); risk difference 0.45 (0.22 to 0.68)).

CONCLUSION

This trial suggests that wearing Tasuki might moderately improve neck pain. With its low-cost, low-risk, and easy-to-use nature, Tasuki could be an option for those who suffer from neck pain.

Making the switch: From case studies to N-of-1 trials

Case studies can generate hypothesis based on unique clinical patient encounters and provide guidance among populations with limited numbers of patients. However, case studies are not blinded and are susceptible to a variety of factors that can influence study outcomes. One potential solution to minimize this bias is to use an N-of-1 trial. N-of-1 trials are a double-blinded randomized crossover trial within a limited number of patients, often as small as a single patient. These trials borrow many concepts from randomized controlled trials (RCTs), which in turn increases the validity of findings compared with a case report. Situations best suited for an N-of-1 trial include chronic disease states and therapies with quick onset and offset, such as in patients with seizures. There are many opportunities to use N-of-1 trials among patients with epilepsy, and providers are encouraged to explore and employ these methods. The purpose of this article was to describe N-of-1 trials along with considerations for conducting, publishing, and evaluating N-of-1 trials.

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The use of N-of-1 trials can minimize bias found in traditional case studies.

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N-of-1 trials are a double-blinded randomized crossover trial within a single patient.

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There are methods and reporting standards to guide the development and interpretation of N-of-1 trials.

The clinical consequences of variable selection in multiple regression models: a case study of the Norwegian Opioid Maintenance Treatment program

Background: Selecting which variables to include in multiple regression models is a pervasive problem in medical research.Objectives: Based on questionnaire data (n = 18538, 69.9% men) from the Norwegian Opioid Maintenance Treatment Program, this study aims to compare the performance of different variable selection methods and the potential clinical consequences of choice of method. The effect of missing data is also explored.Methods: The dependent variable was engagement in criminal behavior while in treatment. Twenty-nine potential covariates on demographics, psychosocial factors and drug use were tested for inclusion in a multiple logistic regression model. Both complete case and multiply imputed data were considered. We compared the results from variable selection methods ranging from expert-based and purposeful variable selection, through stepwise methods, to more recently developed penalized regression using the Least Absolute Shrinkage and Selection Operator (LASSO).Results: The various variable selection methods resulted in regression models including from 9 to 22 covariates. The stepwise selection procedures generated the models with the most covariates included. The choice of variable selection method directly affected the estimated regression coefficients, both in effect size and statistical significance. For several variables the expert-based approach disagreed with all data-driven methods.Conclusions: The choice of variable selection method may strongly affect the resulting regression model, along with accompanying effect sizes and confidence intervals. This may affect clinical conclusions. The process should consequently be given sufficient consideration in model building. We recommend combining expert knowledge with a data-driven variable selection method to explore the models' robustness.

Systematic review on the quality of randomized controlled trials from Saudi Arabia

Background

The quality of randomized controlled trials from Saudi Arabia is unknown since most are observational studies.

Objective

To determine (1) the quantity and quality of randomized controlled trials published from Saudi Arabia, and (2) whether significance of intervention effect varied by study quality.

Methods

PubMed, SCOPUS, and Cochrane were searched with keywords for trials published from Saudi Arabia until February 2018. A total of 422 records were identified and screened, resulting in 61 eligible trials for analysis. Two researchers abstracted trial characteristics and assessed quality in seven domains (randomization, allocation concealment, blinding of assessors or participants, incomplete outcome data, selective reporting, and other sources of bias) using the Cochrane Collaboration Risk of Bias Tool.

Results

A majority of the trials (57%) were published during 2010–2018. High risk of bias was present for blinding (outcome: 13%; participants and personnel: 28%). Biases could not be assessed due to lack of information (unclear risk) in the domains of randomization (54%), allocation concealment (44%), and blinding of outcome assessment (57%). When all seven domains were considered together (summary risk of bias), 0% of the trials had low risk, 39% had high risk, and 61% had unclear risk of biases. A greater proportion of high-risk trials had significant intervention effect than unclear-risk trials (79% vs. 67%).

Conclusion

The volume and quality of trials in Saudi Arabia was low. More high-quality randomized controlled trials are warranted to address chronic diseases.

Mixed exercise training for adults with fibromyalgia

BACKGROUND

Exercise training is commonly recommended for individuals with fibromyalgia. This review is one of a series of reviews about exercise training for fibromyalgia that will replace the review titled "Exercise for treating fibromyalgia syndrome", which was first published in 2002.

OBJECTIVES

To evaluate the benefits and harms of mixed exercise training protocols that include two or more types of exercise (aerobic, resistance, flexibility) for adults with fibromyalgia against control (treatment as usual, wait list control), non exercise (e.g. biofeedback), or other exercise (e.g. mixed versus flexibility) interventions.Specific comparisons involving mixed exercise versus other exercises (e.g. resistance, aquatic, aerobic, flexibility, and whole body vibration exercises) were not assessed.

SEARCH METHODS

We searched the Cochrane Library, MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Thesis and Dissertations Abstracts, the Allied and Complementary Medicine Database (AMED), the Physiotherapy Evidence Databese (PEDro), Current Controlled Trials (to 2013), WHO ICTRP, and ClinicalTrials.gov up to December 2017, unrestricted by language, to identify all potentially relevant trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in adults with a diagnosis of fibromyalgia that compared mixed exercise interventions with other or no exercise interventions. Major outcomes were health-related quality of life (HRQL), pain, stiffness, fatigue, physical function, withdrawals, and adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data, and assessed risk of bias and the quality of evidence for major outcomes using the GRADE approach.

MAIN RESULTS

We included 29 RCTs (2088 participants; 98% female; average age 51 years) that compared mixed exercise interventions (including at least two of the following: aerobic or cardiorespiratory, resistance or muscle strengthening exercise, and flexibility exercise) versus control (e.g. wait list), non-exercise (e.g. biofeedback), and other exercise interventions. Design flaws across studies led to selection, performance, detection, and selective reporting biases. We prioritised the findings of mixed exercise compared to control and present them fully here.Twenty-one trials (1253 participants) provided moderate-quality evidence for all major outcomes but stiffness (low quality). With the exception of withdrawals and adverse events, major outcome measures were self-reported and expressed on a 0 to 100 scale (lower values are best, negative mean differences (MDs) indicate improvement; we used a clinically important difference between groups of 15% relative difference). Results for mixed exercise versus control show that mean HRQL was 56 and 49 in the control and exercise groups, respectively (13 studies; 610 participants) with absolute improvement of 7% (3% better to 11% better) and relative improvement of 12% (6% better to 18% better). Mean pain was 58.6 and 53 in the control and exercise groups, respectively (15 studies; 832 participants) with absolute improvement of 5% (1% better to 9% better) and relative improvement of 9% (3% better to 15% better). Mean fatigue was 72 and 59 points in the control and exercise groups, respectively (1 study; 493 participants) with absolute improvement of 13% (8% better to 18% better) and relative improvement of 18% (11% better to 24% better). Mean stiffness was 68 and 61 in the control and exercise groups, respectively (5 studies; 261 participants) with absolute improvement of 7% (1% better to 12% better) and relative improvement of 9% (1% better to 17% better). Mean physical function was 49 and 38 in the control and exercise groups, respectively (9 studies; 477 participants) with absolute improvement of 11% (7% better to 15% better) and relative improvement of 22% (14% better to 30% better). Pooled analysis resulted in a moderate-quality risk ratio for all-cause withdrawals with similar rates across groups (11 per 100 and 12 per 100 in the control and intervention groups, respectively) (19 studies; 1065 participants; risk ratio (RR) 1.02, 95% confidence interval (CI) 0.69 to 1.51) with an absolute change of 1% (3% fewer to 5% more) and a relative change of 11% (28% fewer to 47% more). Across all 21 studies, no injuries or other adverse events were reported; however some participants experienced increased fibromyalgia symptoms (pain, soreness, or tiredness) during or after exercise. However due to low event rates, we are uncertain of the precise risks with exercise. Mixed exercise may improve HRQL and physical function and may decrease pain and fatigue; all-cause withdrawal was similar across groups, and mixed exercises may slightly reduce stiffness. For fatigue, physical function, HRQL, and stiffness, we cannot rule in or out a clinically relevant change, as the confidence intervals include both clinically important and unimportant effects.We found very low-quality evidence on long-term effects. In eight trials, HRQL, fatigue, and physical function improvement persisted at 6 to 52 or more weeks post intervention but improvements in stiffness and pain did not persist. Withdrawals and adverse events were not measured.It is uncertain whether mixed versus other non-exercise or other exercise interventions improve HRQL and physical function or decrease symptoms because the quality of evidence was very low. The interventions were heterogeneous, and results were often based on small single studies. Adverse events with these interventions were not measured, and thus uncertainty surrounds the risk of adverse events.

AUTHORS' CONCLUSIONS

Compared to control, moderate-quality evidence indicates that mixed exercise probably improves HRQL, physical function, and fatigue, but this improvement may be small and clinically unimportant for some participants; physical function shows improvement in all participants. Withdrawal was similar across groups. Low-quality evidence suggests that mixed exercise may slightly improve stiffness. Very low-quality evidence indicates that we are 'uncertain' whether the long-term effects of mixed exercise are maintained for all outcomes; all-cause withdrawals and adverse events were not measured. Compared to other exercise or non-exercise interventions, we are uncertain about the effects of mixed exercise because we found only very low-quality evidence obtained from small, very heterogeneous trials. Although mixed exercise appears to be well tolerated (similar withdrawal rates across groups), evidence on adverse events is scarce, so we are uncertain about its safety. We downgraded the evidence from these trials due to imprecision (small trials), selection bias (e.g. allocation), blinding of participants and care providers or outcome assessors, and selective reporting.

Adherence to American Cancer Society and American Institute of Cancer Research dietary guidelines in overweight African American breast cancer survivors

PURPOSE

The American Cancer Society (ACS) and the American Institute for Cancer Research (AICR) each created dietary and physical activity guidelines to improve cancer survivorship. Despite African American breast cancer survivors (AABCS) having the lowest survival rates of any racial or ethnic group, limited information exists on their adherence to cancer-specific lifestyle recommendations. The study's purpose was to measure adherence to ACS/AICR dietary recommendations in AABCS.

METHODS

Two hundred ten AABCS enrolled in the Moving Forward intervention trial, a randomized, community-based, 6-month weight loss study, were assessed for socio-demographics, dietary intake (via food frequency questionnaire), and related health factors at baseline. We operationalized the dietary recommendations put forth by ACS/AICR and created component and total adherence index scores. Descriptive statistics were used to calculate the proportion of women who met recommendations. Student's t test and χ2 tests were used to compare participant characteristics by median adherence scores.

RESULTS

The mean total ACS/AICR score was 12.7 ± 2.5 out of 21 points (median, 13; range, 5 to 21). Over 90% were moderately or completely adherent to limiting alcohol and red & processed meat consumption, but the majority failed to meet the other recommendations to eat whole grains, legumes, fruits, vegetables, and avoid added sugars. Women with total scores below the median were younger, with higher BMI, had fewer years of education, and lower income levels.

IMPLICATIONS FOR CANCER SURVIVORS

The present study extends the literature on AABCS adherence to cancer survivor-specific dietary guidelines. Findings will inform future dietary lifestyle interventions in this population.

The role of the randomised controlled trial in restorative dentistry and the correct purpose of observational data

It has been argued that the randomised controlled trial design is unsuitable for restorative dentistry and that cohort studies or the analysis of large observational datasets without randomisation is more suitable. This opinion article examines why randomisation in clinical trials is needed and why big observational data is not enough for clinical inference.