Randomized versus historical controls for clinical trials

Retrieval Practice Improves Exam Performance as a Function of Review Question Number and Format

INTRODUCTION

Although retrieval practice is a well-established method of improving learning, it is unclear whether review question format matters or how many review questions are needed to maximize the effects of retrieval practice.

REVIEW OF LITERATURE

Inconsistent findings are reported regarding review question format, and no studies were conducted in physical therapy education programs. A positive relationship is reported between review question number and exam performance, but no studies estimate the number of review questions needed to maximize retention of specific learning objectives.

SUBJECTS

Eighty-eight second-year Doctor of Physical Therapy students (baseline cohort = 42 students, intervention cohort = 46 students).

METHODS

Exam questions were randomly assigned into different review categories. Some exam questions received no review, whereas other exam questions were reviewed with open-ended review questions or varying numbers of multiple-choice review questions. Performance on 160 multiple-choice exam questions was compared between review question categories using mixed-effects logistic regression models.

RESULTS

Both open-ended and multiple-choice review questions significantly improved exam question performance. Performance on exam questions improved most when more than one multiple-choice review question was provided. After controlling for exam question difficulty, multiple-choice review questions were superior to open-ended review questions.

DISCUSSION AND CONCLUSION

On multiple-choice exams, multiple-choice review questions are at least as effective as open-ended review questions. Given their ease of implementation, multiple-choice review questions are an efficient means to improve multiple-choice exam question performance.

The effects of exercise training on inflammatory markers in children and adolescents: A systematic review and meta-analysis

INTRODUCTION AND AIM

Exercise training is effective for improving cardiometabolic health in children and adolescents, but less is known about its impact on inflammatory markers. We therefore, undertook a systematic review and meta-analysis to investigate the role of exercise training on pro-inflammatory cytokines including interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) in children and adolescents.

METHOD

A comprehensive search was conducted in three electronic databases including PubMed, Web of Science, and Scopus, from inception to December 2023 to identify exercise trials with and without control groups, involving participants with mean ages ranging from ≥ 6 to < 18 years, of age with measurements of at least one of the following pro-inflammatory cytokines IL-6, TNF-α, or CRP. Standardized mean differences (SMD) and 95 % confidence interval (ICs) were calculated using random effects models.

RESULTS

Thirty-eight studies involving 2043 children and adolescents were included. The results show that exercise training resulted in significant reductions in IL-6 [SMD: -0.44; 95 % CI: -0.68, -0.21; P = 0.001] and CRP [SMD: -0.28; 95 % CI: -0.41, -0.16; P = 0.001], but not TNF-α [SMD: -0.15; 95 % CI: -0.38, -0.07; P = 0.19]. Subgroup analyses showed that IL-6 and CRP were reduced with aerobic training in adolescents, as was CRP with high-intensity interval training.

CONCLUSION

These results provide evidence that exercise training is effective for reducing IL-6 and CRP in adolescents, but not in children, and any benefits may be modulated by the type of exercise performed.

A diagnostic phase III/IV seamless design to investigate the diagnostic accuracy and clinical effectiveness using the example of HEDOS and HEDOS II

The development process of medical devices can be streamlined by combining different study phases. Here, for a diagnostic medical device, we present the combination of confirmation of diagnostic accuracy (phase III) and evaluation of clinical effectiveness regarding patient-relevant endpoints (phase IV) using a seamless design. This approach is used in the Thyroid HEmorrhage DetectOr Study (HEDOS & HEDOS II) investigating a post-operative hemorrhage detector named ISAR-M THYRO® in patients after thyroid surgery. Data from the phase III trial are reused as external controls in the control group of the phase IV trial. An unblinded interim analysis is planned between the two study stages which includes a recalculation of the sample size for the phase IV part after completion of the first stage of the seamless design. The study concept presented here is the first seamless design proposed in the field of diagnostic studies. Hence, the aim of this work is to emphasize the statistical methodology as well as feasibility of the proposed design in relation to the planning and implementation of the seamless design. Seamless designs can accelerate the overall trial duration and increase its efficiency in terms of sample size and recruitment. However, careful planning addressing numerous methodological and procedural challenges is necessary for successful implementation as well as agreement with regulatory bodies.

Treatment effect estimation using the propensity score in clinical trials with historical control

BACKGROUND

Clinical trials assessing new treatment effects require a control group to compare the pure treatment effects. However, in clinical trials on regenerative medicine, rare diseases, and intractable diseases, it may be ethically difficult to assign participants to the control group. In recent years, the use of historical control data has attracted attention as a method for supplementing the number of participants in the control group. When combining historical control data with new randomized controlled trial (RCT) data, the assessment of heterogeneity using outcome data is not sufficient. Therefore, several statistical methods that consider participant outcomes and baseline characteristics, including the propensity score (PS) method have been proposed.

METHODS

We propose a new method considering "information on whether the data are RCT data or not" in the PS model when combining the RCT and historical control data. The performance of the proposed method in estimating the treatment effect is evaluated using simulation data.

RESULTS

When the distribution of covariates is similar between the RCT and historical control data, not much difference in performance is found between the proposed and conventional methods to estimate the treatment effect. On the other hand, when the distribution of covariates is not similar between the two kinds of data, the proposed method shows higher performance.

CONCLUSIONS

Even when it is not known whether RCT and historical control data are similar, the proposed PS model is useful to estimate the treatment effect appropriately in RCTs using historical control data.

Uncontrolled pain: a call for better study design

Studies assessing animal pain in veterinary research are often performed primarily for the benefit of animals. Frequently, the goal of these studies is to determine whether the analgesic effect of a novel treatment is clinically meaningful, and therefore has the capacity to improve the welfare of treated animals. To determine the treatment effect of a potential analgesic, control groups are necessary to allow comparison. There are negative control groups (where pain is unattenuated) and positive control groups (where pain is attenuated). Arising out of animal welfare concerns, there is growing reluctance to use negative control groups in pain studies. But for studies where pain is experimentally induced, the absence of a negative control group removes the opportunity to demonstrate that the study methods could differentiate a positive control intervention from doing nothing at all. For studies that are controlled by a single comparison group, the capacity to distinguish treatment effects from experimental noise is more difficult; especially considering that pain studies often involve small sample sizes, small and variable treatment effects, systematic error and use pain assessment measures that are unreliable. Due to these limitations, and with a focus on farm animals, we argue that many pain studies would be enhanced by the simultaneous inclusion of positive and negative control groups. This would help provide study-specific definitions of pain and pain attenuation, thereby permitting more reliable estimates of treatment effects. Adoption of our suggested refinements could improve animal welfare outcomes for millions of animals globally.

Best-Evidence Systematic Review and Meta-Analysis of Mini-Open Carpal Tunnel Release

Purpose

This study aimed to evaluate the safety and effectiveness of mini-open carpal tunnel release (mOCTR) using best-evidence synthesis methods.

Methods

We systematically searched for prospective studies published from January 2013 to July 2023 that reported outcomes from a minimum of 50 mOCTR cases. The outcomes included Quick Disabilities of the Arm, Shoulder, and Hand Questionnaire, Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQ-SSS) and Functional Status Scale (BCTQ-FSS), pain visual analog scale (VAS), complication rate, and reoperation rate. Data analysis was performed using a random-effects meta-analysis, with metaregression to identify the associations between patient- and study-level factors with surgical outcomes.

Results

The meta-analysis included 23 studies with 2,303 patients followed for median durations ranging from 6 to 12 months depending on the outcome. Mini-open carpal tunnel release resulted in statistically significant and clinically important improvements in Quick Disabilities of the Arm, Shoulder, and Hand Questionnaire (mean difference = -25.5; 95% confidence interval [CI]: -36.4 to -14.5; P < .001), BCTQ-SSS (mean difference = -2.2; 95% CI: -2.5 to -1.9; P < .001), BCTQ-FSS (mean difference = -2.1; 95% CI: -2.4 to -1.7; P < .001), and pain VAS (mean difference = -5.1; 95% CI: -6.2 to -4.1; P < .001). The sole predictor of improvement in BCTQ-SSS, BCTQ-FSS, and pain VAS was a higher preoperative score for the respective variable (all P < .001). The risk of complications (mainly short-term pillar pain or scar complications) was 8.9% (95% CI: 4.0%-13.8%) and increased with longer incision lengths (P = .008). Revision carpal tunnel release was performed in 0.6% (95% CI: 0.1%-1.0%) of the cases during follow-up. No cases of median nerve transection were reported.

Conclusions

Based on a best-evidence meta-analysis of contemporary studies, mOCTR significantly improved function and pain, with a relatively low risk of mainly temporary complications. Patient outcomes after mOCTR were influenced by patient symptomatology and surgical incision length.

Clinical relevance

Mini-open carpal tunnel release is an effective surgical option that significantly improves symptoms and function, especially for patients with more severe baseline dysfunction. Surgeons should use the shortest incision that allows adequate visualization to safely divide the transverse carpal ligament.

Study design approaches for future active-controlled HIV prevention trials

Objectives

Vigorous discussions are ongoing about future efficacy trial designs of candidate human immunodeficiency virus (HIV) prevention interventions. The study design challenges of HIV prevention interventions are considerable given rapid evolution of the prevention landscape and evidence of multiple modalities of highly effective products; future trials will likely be 'active-controlled', i.e., not include a placebo arm. Thus, novel design approaches are needed to accurately assess new interventions against these highly effective active controls.

Methods

To discuss active control design challenges and identify solutions, an initial virtual workshop series was hosted and supported by the International AIDS Enterprise (October 2020-March 2021). Subsequent symposia discussions continue to advance these efforts. As the non-inferiority design is an important conceptual reference design for guiding active control trials, we adopt several of its principles in our proposed design approaches.

Results

We discuss six potential study design approaches for formally evaluating absolute prevention efficacy given data from an active-controlled HIV prevention trial including using data from: 1) a registrational cohort, 2) recency assays, 3) an external trial placebo arm, 4) a biomarker of HIV incidence/exposure, 5) an anti-retroviral drug concentration as a mediator of prevention efficacy, and 6) immune biomarkers as a mediator of prevention efficacy.

Conclusions

Our understanding of these proposed novel approaches to future trial designs remains incomplete and there are many future statistical research needs. Yet, each of these approaches, within the context of an active-controlled trial, have the potential to yield reliable evidence of efficacy for future biomedical interventions.

Anakinra authorized to treat severe coronavirus disease 2019; Sepsis breakthrough or time to reflect?

Introduction

The European Medicines Agency (EMA) and the United States Food and Drug Administration (FDA) announced conditions for using recombinant human interleukin-1 receptor antagonist (rhIL-1ra) to treat hospitalized patients with Coronavirus disease 2019 (COVID-19) and risk for progression. These decisions followed publication of the suPAR-guided Anakinra treatment for Validation of the risk and early Management OF seveRE respiratory failure by COVID-19 (SAVE- MORE) phase 3 clinical trial that yielded positive results.

Methods

We conducted a literature review and theoretical analysis of IL-1 blockade as a therapy to treat COVID-19. Using a stepwise analysis, we assessed clinical applicability of the SAVE-MORE results and evaluated conceptual support for interleukin-1 suppression as a suitable approach to COVID-19 treatment. This therapeutic approach was then examined as an example of inflammation-suppressing measures used to treat sepsis.

Results

Anakinra use as a COVID-19 therapy seems to rely on a view of pathogenesis that incorrectly reflects human disease. Since COVID-19 is an example of sepsis, COVID-19 benefit due to anti-inflammatory therapy contradicts an extensive history of unsuccessful clinical study. Repurposing rhIL-1ra to treat COVID-19 appears to exemplify a cycle followed by inflammation-suppressing sepsis treatments. A landscape of treatment failures is interrupted by a successful clinical trial. However, subsequent confirmatory study fails to replicate the positive data.

Discussion

We suggest further experimentation is not a promising pathway to discover game-changing sepsis therapies. A different kind of approach may be necessary.

Coronary artery bypass grafting using bilateral internal thoracic arteries in patients with diabetes and obesity: A systematic review and meta-analysis

Background

Patients with diabetes and obesity are at higher risk of adverse long-term outcomes following coronary artery bypass grafting. The use of bilateral internal thoracic arteries (BITA) can potentially offer survival benefit in higher risk patients compared to single internal thoracic artery (SITA), but BITA is not routinely used due to lack of clear evidence of efficacy and concerns over sternal wound complications.

Methods

Medline, Embase and the Cochrane Library were searched for studies comparing the efficacy and safety of BITA and SITA grafting in patients with diabetes and obesity. Meta-analysis of mortality and sternal wound complications was performed.

Results

We identified eight observational and ten propensity matched studies, and one RCT, comparing BITA and SITA which included patients with diabetes (n = 19,589); two propensity matched studies and one RCT which included patients with obesity (n = 6,972); mean follow up was 10.5 and 11.3 years respectively. Meta-analysis demonstrated a mortality reduction for BITA compared to SITA in patients with diabetes (risk ratio [RR] 0.79; 95% confidence interval [CI] 0.70-0.90; p = 0.0003). In patients with obesity there was a non-significant reduction in mortality in the BITA group (RR 0.73, 95% CI 0.47-1.12; p = 0.15). There was a significantly higher rate of sternal wound complications following BITA observed in patients with diabetes (RR 1.53, 95% CI 1.23-1.90; p = 0.0001) and obesity (RR 2.24, 95% CI 1.63-3.07; p < 0.00001).

Conclusions

BITA is associated with better long-term survival in patients with diabetes. The effects of BITA grafting in patients with obesity are uncertain. BITA is associated with higher rates of sternal wound complications compared to SITA in both patients with diabetes and obesity.

Guidance on interim analysis methods in clinical trials

Interim analyses in clinical trials can take on a multitude of forms. They are often used to guide Data and Safety Monitoring Board (DSMB) recommendations to study teams regarding recruitment targets for large, later-phase clinical trials. As collaborative biostatisticians working and teaching in multiple fields of research and across a broad array of trial phases, we note the large heterogeneity and confusion surrounding interim analyses in clinical trials. Thus, in this paper, we aim to provide a general overview and guidance on interim analyses for a nonstatistical audience. We explain each of the following types of interim analyses: efficacy, futility, safety, and sample size re-estimation, and we provide the reader with reasoning, examples, and implications for each. We emphasize that while the types of interim analyses employed may differ depending on the nature of the study, we would always recommend prespecification of the interim analytic plan to the extent possible with risk mitigation and trial integrity remaining a priority. Finally, we posit that interim analyses should be used as tools to help the DSMB make informed decisions in the context of the overarching study. They should generally not be deemed binding, and they should not be reviewed in isolation.

Is it feasible and ethical to randomize patients between surgery and non-surgical treatments for gastrointestinal cancers?

Background

In several settings in the treatment of gastrointestinal cancers, it is unclear if the addition of surgery to a multimodal treatment strategy, or in some circumstances its omission, lead to a better outcome for patients. In such situations of clinical equipoise, high-quality evidence from randomised-controlled trials is needed to decide which treatment approach is preferable.

Objective

In this article, we outline the importance of randomised trials comparing surgery with non-surgical therapies for specific scenarios in the treatment of gastrointestinal cancers. We explain the difficulties and solutions of designing these trials and recruiting patients in this context.

Methods

We performed a selective review based on a not systematic literature search in core databases, supplemented by browsing health information journals and citation searching. Only articles in English were selected. Based on this search, we discuss the results and methodological characteristics of several trials which randomised patients with gastrointestinal cancers between surgery and non-surgical treatments, highlighting their differences, advantages, and limitations.

Results and conclusions

Innovative and effective cancer treatment requires randomised trials, also comparing surgery and non-surgical treatments for defined scenarios in the treatment of gastrointestinal malignancies. Nevertheless, potential obstacles to designing and carrying out these trials must be recognised ahead of time to avoid problems before or during the trial.

Natural experiments for orthopaedic trauma research: An introduction

Natural experiments are observational studies of medical treatments in which treatment allocation is determined by factors outside the control of the investigators, arguably resembling experimental randomisation. Natural experiments in the field of orthopaedic trauma research are scarce. However, they have great potential due to the process governing treatment allocation and the existence of opposing treatment strategies between hospitals or between regions as a result of local education, conviction, or cultural and socio-economic factors. Here, the possibilities and opportunities of natural experiments in the orthopaedic trauma field are discussed. Potential solutions are presented to improve the validity of natural experiments and how to assess the credibility of such studies. Above all, it is meant to spark a discussion about its role within the field of orthopaedic trauma research.

Use of Bayesian Statistics to Reanalyze Data From the Pragmatic Randomized Optimal Platelet and Plasma Ratios Trial

IMPORTANCE

Frequentist statistical approaches are the most common strategies for clinical trial design; however, bayesian trial design may provide a more optimal study technique for trauma-related studies.

OBJECTIVE

To describe the outcomes of bayesian statistical approaches using data from the Pragmatic Randomized Optimal Platelet and Plasma Ratios (PROPPR) Trial.

DESIGN, SETTING, AND PARTICIPANTS

This quality improvement study performed a post hoc bayesian analysis of the PROPPR Trial using multiple hierarchical models to assess the association of resuscitation strategy with mortality. The PROPPR Trial took place at 12 US level I trauma centers from August 2012 to December 2013. A total of 680 severely injured trauma patients who were anticipated to require large volume transfusions were included in the study. Data analysis for this quality improvement study was conducted from December 2021 and June 2022.

INTERVENTIONS

In the PROPPR Trial, patients were randomized to receive a balanced transfusion (equal portions of plasma, platelets, and red blood cells [1:1:1]) vs a red blood cell-heavy strategy (1:1:2) during their initial resuscitation.

MAIN OUTCOMES AND MEASURES

Primary outcomes from the PROPPR trial included 24-hour and 30-day all-cause mortality using frequentist statistical methods. Bayesian methods were used to define the posterior probabilities associated with the resuscitation strategies at each of the original primary end points.

RESULTS

Overall, 680 patients (546 [80.3%] male; median [IQR] age, 34 [24-51] years, 330 [48.5%] with penetrating injury; median [IQR] Injury Severity Score, 26 [17-41]; 591 [87.0%] with severe hemorrhage) were included in the original PROPPR Trial. Between the groups, no significant differences in mortality were originally detected at 24 hours (12.7% vs 17.0%; adjusted risk ratio [RR], 0.75 [95% CI, 0.52-1.08]; P = .12) or 30 days (22.4% vs 26.1%; adjusted RR, 0.86 [95% CI, 0.65-1.12]; P = .26). Using bayesian approaches, a 1:1:1 resuscitation was found to have a 93% (Bayes factor, 13.7; RR, 0.75 [95% credible interval, 0.45-1.11]) and 87% (Bayes factor, 6.56; RR, 0.82 [95% credible interval, 0.57-1.16]) probability of being superior to a 1:1:2 resuscitation with regards to 24-hour and 30-day mortality, respectively.

CONCLUSIONS AND RELEVANCE

In this quality improvement study, a post hoc bayesian analysis of the PROPPR Trial found evidence in support of mortality reduction with a balanced resuscitation strategy for patients in hemorrhagic shock. Bayesian statistical methods offer probability-based results capable of direct comparison between various interventions and should be considered for future studies assessing trauma-related outcomes.

Causal inference for longitudinal data based on historical controls

Use of historical data has become a hot topic recently, considered to provide a way to reduce patient burden, lower drug development cost, and make innovative therapies available to patients earlier. In a single-arm study designed to examine the benefit of an experimental treatment, there is often a desire to compare the outcomes of patients receiving the new intervention with those receiving a control treatment, which can be extracted from sources such as historical trials or electronic medical records. Since the treatment is not randomly assigned, there is a need to adjust for the potential imbalance in key patient characteristics between the current study and historical controls. If the outcome of interest is measured longitudinally and subject to random missing, the required adjustment becomes more complicated. In this paper, we propose a doubly robust adjustment procedure specifically designed for longitudinal data analysis with missing data. The proposed method yields valid analysis results, if either the propensity score model or the mixed effects model for repeated measures (MMRM) regression model is correctly specified. An extensive numerical study is conducted to examine the performance of the proposed method. Data from a real clinical trial comparing with historical data are analyzed as an example applying the proposed procedure.

Norepinephrine may improve survival of septic shock patients in a low-resource setting: a proof-of-concept study on feasibility and efficacy outside the Intensive Care Unit

Septic shock treatment in sub-Saharan African hospitals is challenging due to limited availability of ICUs, central venous catheters, vasopressors, and trained staff. We designed this proof-of-concept study to determine efficacy, safety, and feasibility of norepinephrine (NE) use in a non-intensive setting in a low-resource country, consisting in a peripheral infusion via a mechanical drop counter. Septic shock patients accessing a rural hospital in Uganda were included: the 2020 group (N = 12) was prospectively enrolled (Jan-Mar 2020) when NE was available; the 2019 group (N = 11) was retrospectively enrolled (Oct-Dec 2019). Enrollment was continuous to reduce selection bias. Basic clinical endpoints (noninvasive blood pressure, tissue perfusion, diuresis) defined shock control and the prognostic endpoint was survival at hospital discharge. Shock control at 6 and 12 hours was higher in the 2020 group (p = 0.012 for both). Survival at hospital discharge was 75% and 27.3%, respectively (p = 0.039). NE infusion was associated with a Hazard Ratio of 0.23 (p = 0.041) in a multivariate Cox model. No NE-induced adverse effects were detected. These preliminary results suggest that implementing NE infusion in a low-resource setting without ICU could be a safe and effective strategy in managing septic shock and that this approach could lead to a lower mortality rate.

Risk factors for early death or euthanasia within 100 days of diagnosis in dogs with meningoencephalitis of unknown origin

Meningoencephalitis of unknown origin (MUO) in the dog is an inflammatory condition of the central nervous system with variable short- and long-term prognosis. Previous studies have attempted to identify risk factors for early death; however, the findings were inconsistent and prognostication and treatment selection remain difficult for cases of MUO. The aim of this study was to compare the influence of putative prognostic factors on early survival in dogs with MUO. Logistic regression was used to analyse the effect of clinical and magnetic resonance imaging (MRI) features at diagnosis and type of immune-suppressive treatment received on survival at three-time points; 7 days, 30 days, and 100 days post-diagnosis. Ninety eight dogs were included. Dogs that were obtunded at presentation had a 6.6 times increased odds of death in the first 7 days after diagnosis, a 2.1 times increased risk of death 8-30 days after diagnosis, and a 1.9 times increased risk of death 31-100 days after diagnosis. No other clinical, MRI feature, or treatment was found to have a significant influence on survival. Obtundation at presentation was found to increase risk of early euthanasia in dogs with MUO, while the addition of an IV infusion of cytarabine to immune-suppressive corticosteroid therapy (prednisolone and/or dexamethasone) at initial treatment did not improve the odds of survival at 7, 30, or 100 days after diagnosis.

Exercise and Cardiovascular Disease Risk Factors in Children and Adolescents With Obesity: A Systematic Review With Meta-Analysis of Randomized Controlled Trials

The purpose of this study was to examine the effects of exercise on cardiovascular disease (CVD) risk factors in children and adolescents with obesity. Randomized controlled trials (RCTs) of exercise ≥4 weeks in children and adolescents with obesity were included if one or more CVD risk factors were included as an outcome. Studies were retrieved by searching 7 electronic databases, cross-referencing, and expert review. Data were pooled using the inverse-variance heterogeneity (IVhet) model and strength of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) instrument. Thirty-nine studies representing 1548 participants (847 exercise, 701 control) met the inclusion criteria. Aerobic exercise improved 10 of 12 (83.3%) outcomes (P < .05 for all) while combined aerobic and strength training improved 5 of 8 (62.5%) outcomes (P < .05 for all). The strength of evidence ranged from "very low" to "moderate." It was concluded that aerobic exercise, as well as combined aerobic and strength training, is associated with improvements in multiple CVD risk factors among children and adolescents with obesity. However, the generally low strength of evidence suggests a need for future well-designed and conducted RCTs on the effects of exercise, especially strength training, in children and adolescents with obesity.

Perioperative care bundles for the prevention of surgical-site infections: meta-analysis

BACKGROUND

Care bundles are used widely to prevent surgical-site infections (SSIs). Recent systematic reviews suggested larger effects from bundles with more interventions. These reviews were largely based on uncontrolled before-after studies and did not consider their biases. The aim of this meta-analysis was to determine the effectiveness of care bundles to prevent SSIs and explore characteristics of effective care bundles.

METHODS

A systematic review, reanalysis, and meta-analysis of available evidence were undertaken. RCTs, controlled before-after studies, and uncontrolled before-after studies with sufficient data for reanalysis as interrupted time series studies (ITS) were eligible. Studies investigating the use of a care bundle, with at least one intraoperative intervention, compared with standard care were included.

RESULTS

Four RCTs, 1 controlled before-after study, and 13 ITS were included. Pooled data from RCTs were heterogeneous. Meta-analysis of ITS resulted in a level change of -1.16 (95 per cent c.i.-1.78 to -0.53), indicating a reduction in SSI. The effect was larger when the care bundle comprised a higher proportion of evidence-based interventions. Meta-regression analyses did not show statistically significant associations between effect estimates and number of interventions, number of evidence-based interventions, or proportion of evidence-based interventions.

CONCLUSION

Meta-analysis of ITS indicated that perioperative care bundles prevent SSI.This effect is inconsistent across RCTs. Larger bundles were not associated with a larger effect, but the effect may be larger if the care bundle contains a high proportion of evidence-based interventions. No strong evidence for characteristics of effective care bundles was identified.

Population scale latent space cohort matching for the improved use and exploration of observational trial data

A significant amount of clinical research is observational by nature and derived from medical records, clinical trials, and large-scale registries. While there is no substitute for randomized, controlled experimentation, such experiments or trials are often costly, time consuming, and even ethically or practically impossible to execute. Combining classical regression and structural equation modeling with matching techniques can leverage the value of observational data. Nevertheless, identifying variables of greatest interest in high-dimensional data is frequently challenging, even with application of classical dimensionality reduction and/or propensity scoring techniques. Here, we demonstrate that projecting high-dimensional medical data onto a lower-dimensional manifold using deep autoencoders and post-hoc generation of treatment/control cohorts based on proximity in the lower-dimensional space results in better matching of confounding variables compared to classical propensity score matching (PSM) in the original high-dimensional space (P<0.0001) and performs similarly to PSM models constructed by experts with prior knowledge of the underlying pathology when evaluated on predicting risk ratios from real-world clinical data. Thus, in cases when the underlying problem is poorly understood and the data is high-dimensional in nature, matching in the autoencoder latent space might be of particular benefit.

Effect of interbody fusion compared with posterolateral fusion on lumbar degenerative spondylolisthesis: a systematic review and meta-analysis

BACKGROUND CONTEXT

Lumbar degenerative spondylolisthesis is a relatively common pathology, and surgical treatment is an option in selected cases. The common use of anterior column support by interbody fusion (IBF) has not been adequately studied.

PURPOSE

The primary objective of this systematic review and meta-analysis was to compare the functional and surgical outcomes after posterolateral fusion (PLF) and IBF for the treatment of degenerative spondylolisthesis.

STUDY DESIGN

A systematic review and meta-analysis was conducted to identify studies analyzing the effects of IBF compared to those of instrumented PLF on degenerative spondylolisthesis.

PATIENT SAMPLE

A total of 1,063 patients were included in the analysis. Of them, 470 patients were treated with PLF and 593 with IBF.

OUTCOME MEASURES

The outcomes analyzed were the visual analog scale and numerical rating scale scores for back pain, Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36) score, 12-Item Short Form Health Survey (physical and mental components) score, blood loss amount, surgical time, hospital stay duration, fusion rate, lumbar lordosis, sacral slope, and postoperative complications.

METHODS

A search was conducted using the MEDLINE, Cochrane, and Google Scholar databases for studies published between January 1985 and February 2021. Both retrospective and prospective studies that compared between IBF and PLF were included.

RESULTS

A total of 2,819 articles were screened, and 38 full-text articles were selected for a detailed investigation, of which 12 articles were found to match all the inclusion criteria and were included in the meta-analysis. There was an improvement in the sacral slope (mean difference [MD] = 3 [95% confidence interval {CI} = 0.83-5.17]) and fusion rate (odds ratio [OR] = 0.47 [95% CI = 0.26-0.86]) in the IBF group. The incidence of neural injury was higher in the IBF group (OR = 0.28 [95% CI = 0.13-0.60]) than in the PLF group. There were no differences in the back pain scores, ODI, SF-36 score, blood loss amount, surgical time, hospital stay duration, lumbar lordosis, infection, and durotomy between the groups.

CONCLUSIONS

IBF for the treatment of lumbar degenerative spondylolisthesis showed better results in terms of the fusion rate and sacral slope, but which did not translate into better clinical outcomes. Further randomized and prospective studies are necessary to elucidate the optimal therapeutic options.

The neurologic pain signature responds to nonsteroidal anti-inflammatory treatment vs placebo in knee osteoarthritis

Supplemental Digital Content is Available in the Text.

fMRI-based measures, validated for nociceptive pain, respond to acute osteoarthritis pain, are not sensitive to placebo, and are mild-to-moderately sensitive to naproxen.

Introduction:

Many drug trials for chronic pain fail because of high placebo response rates in primary endpoints. Neurophysiological measures can help identify pain-linked pathophysiology and treatment mechanisms. They can also help guide early stop/go decisions, particularly if they respond to verum treatment but not placebo. The neurologic pain signature (NPS), an fMRI-based measure that tracks evoked pain in 40 published samples and is insensitive to placebo in healthy adults, provides a potentially useful neurophysiological measure linked to nociceptive pain.

Objectives:

This study aims to validate the NPS in knee osteoarthritis (OA) patients and test the effects of naproxen on this signature.

Methods:

In 2 studies (50 patients, 64.6 years, 75% females), we (1) test the NPS and other control signatures related to negative emotion in knee OA pain patients; (2) test the effect of placebo treatments; and (3) test the effect of naproxen, a routinely prescribed nonsteroidal anti-inflammatory drug in OA.

Results:

The NPS was activated during knee pain in OA (d = 1.51, P < 0.001) and did not respond to placebo (d = 0.12, P = 0.23). A single dose of naproxen reduced NPS responses (vs placebo, NPS d = 0.34, P = 0.03 and pronociceptive NPS component d = 0.38, P = 0.02). Naproxen effects were specific for the NPS and did not appear in other control signatures.

Conclusion:

This study provides preliminary evidence that fMRI-based measures, validated for nociceptive pain, respond to acute OA pain, do not appear sensitive to placebo, and are mild-to-moderately sensitive to naproxen.

Predictable Clinical Benefits without Evidence of Synergy in Trials of Combination Therapies with Immune-Checkpoint Inhibitors

PURPOSE

Combinations of immune-checkpoint inhibitors (ICI) with other cancer therapies have been approved for advanced cancers in multiple indications, and numerous trials are under way to test new combinations. However, the mechanisms that account for the superiority of approved ICI combinations relative to their constituent monotherapies remain unknown.

EXPERIMENTAL DESIGN

We analyzed 13 phase III clinical trials testing combinations of ICIs with each other or other drugs in patients with advanced melanoma and lung, breast, gastric, kidney, and head and neck cancers. The clinical activity of the individual constituent therapies, measured in the same or a closely matched trial cohort, was used to compute progression-free survival (PFS) curves expected under a model of independent drug action. To identify additive or synergistic efficacy, PFS expected under this null model was compared with observed PFS by Cox regression.

RESULTS

PFS elicited by approved combination therapies with ICIs could be accurately predicted from monotherapy data using the independent drug action model (Pearson r = 0.98, P < 5 × 10^-9, N = 4,173 patients, 8 types of cancer). We found no evidence of drug additivity or synergy except in one trial in which such interactions might have extended median PFS by 9 days.

CONCLUSIONS

Combining ICIs with other cancer therapies affords predictable and clinically meaningful benefit by providing patients with multiple chances of response to a single agent. Conversely, there exists no evidence in phase III trials that other therapies interact with and enhance the activity of ICIs. These findings can inform the design and testing of new ICI combination therapies while emphasizing the importance of developing better predictors (biomarkers) of ICI response.

The Effects of Exercise on Bone Mineral Density in Men: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

The aim of this systematic review and meta-analysis was to provide an updated analysis, including the use of more robust methods, on the effects of exercise on bone mineral density in men. Randomised Control Trials of > 24 weeks and published in English up to 01/05/20 were retrieved from 3 electronic databases, cross-referencing, and expert review. The primary outcome measures were changes in FN, LS, and lower limb BMD Standardised effect sizes were calculated from each study and pooled using the inverse heterogeneity model. A statistically significant benefit of exercise was observed on FN BMD [g = 0.21 (0.03, 0.40), Z = 2.23 p = 0.03], with no observed statistically significant benefit of exercise on LS BMD [g = 0.10 (- 0.07, 0.26), Z = 1.15 p = 0.25]. This analysis provided additional evidence to recommend ground- and/or joint-reaction force exercises for improving or maintaining FN, but not LS BMD. Additional well-designed RCTs are unlikely to alter this evidence, although interventions that include activities that directly load the lumbar spine are needed to ensure this is not a potential method of improving LS BMD.

Radiation Proctitis: The Potential Role of Hyaluronic Acid in the Prevention and Restoration of Any Damage to the Rectal Mucosa among Prostate Cancer Patients Submitted to Curative External Beam Radiotherapy

Aim: To evaluate if hyaluronic acid reduces proctitis episodes with respect to corticosteroids in prostate cancer patients submitted to radical or adjuvant radiotherapy. Methods: A consecutive series of eligible patients received hyaluronic acid enemas as supportive care (experimental group, from January 2013 to June 2015). A historical group (control group), treated from October 2011 to December 2012, received beclomethasone dipropionate suppositories. We registered each patient’s data regarding acute and chronic proctitis. All patients were treated with static-intensity-modulated radiotherapy coupled to a daily set-up verification with orthogonal anterior–posterior/lateral X-ray pairs. Results: A total of 269 patients, 175 in the experimental group and 94 in the control group, was evaluated; 2 Gy/day (up to a total median dose of 80 Gy) and 2.7 Gy/day (up to a total median dose of 67.5 Gy) fractionation schemes were used for 216 and 53 patients, respectively. All patients had a good tolerance to radiotherapy, reporting no G3 or greater proctitis. No significant difference was reported concerning the total rate of proctitis between the two groups but only with respect to its grade: a higher G2 rate within the control group. There was no correlation between daily dose fractionation and toxicity grade. Conclusions: Hyaluronic acid enemas might be effective in reducing the severity of radiation proctitis.

Apophenia and anesthesia: how we sometimes change our practice prematurely

Human beings are predisposed to identifying false patterns in statistical noise, a likely survival advantage during our evolutionary development. Moreover, humans seem to prefer "positive" results over "negative" ones. These two cognitive features lay a framework for premature adoption of falsely positive studies. Added to this predisposition is the tendency of journals to "overbid" for exciting or newsworthy manuscripts, incentives in both the academic and publishing industries that value change over truth and scientific rigour, and a growing dependence on complex statistical techniques that some reviewers do not understand. The purpose of this article is to describe the underlying causes of premature adoption and provide recommendations that may improve the quality of published science.

Validity of observational evidence on putative risk and protective factors: appraisal of 3744 meta-analyses on 57 topics

BACKGROUND

The validity of observational studies and their meta-analyses is contested. Here, we aimed to appraise thousands of meta-analyses of observational studies using a pre-specified set of quantitative criteria that assess the significance, amount, consistency, and bias of the evidence. We also aimed to compare results from meta-analyses of observational studies against meta-analyses of randomized controlled trials (RCTs) and Mendelian randomization (MR) studies.

METHODS

We retrieved from PubMed (last update, November 19, 2020) umbrella reviews including meta-analyses of observational studies assessing putative risk or protective factors, regardless of the nature of the exposure and health outcome. We extracted information on 7 quantitative criteria that reflect the level of statistical support, the amount of data, the consistency across different studies, and hints pointing to potential bias. These criteria were level of statistical significance (pre-categorized according to 10^-6, 0.001, and 0.05 p-value thresholds), sample size, statistical significance for the largest study, 95% prediction intervals, between-study heterogeneity, and the results of tests for small study effects and for excess significance.

RESULTS

3744 associations (in 57 umbrella reviews) assessed by a median number of 7 (interquartile range 4 to 11) observational studies were eligible. Most associations were statistically significant at P < 0.05 (61.1%, 2289/3744). Only 2.6% of associations had P < 10^-6, ≥1000 cases (or ≥20,000 participants for continuous factors), P < 0.05 in the largest study, 95% prediction interval excluding the null, and no large between-study heterogeneity, small study effects, or excess significance. Across the 57 topics, large heterogeneity was observed in the proportion of associations fulfilling various quantitative criteria. The quantitative criteria were mostly independent from one another. Across 62 associations assessed in both RCTs and in observational studies, 37.1% had effect estimates in opposite directions and 43.5% had effect estimates differing beyond chance in the two designs. Across 94 comparisons assessed in both MR and observational studies, such discrepancies occurred in 30.8% and 54.7%, respectively.

CONCLUSIONS

Acknowledging that no gold-standard exists to judge whether an observational association is genuine, statistically significant results are common in observational studies, but they are rarely convincing or corroborated by randomized evidence.

Importance of Internal Variability in Clinical Trials of Cardiovascular Disease

A well conducted randomised controlled trial (RCT) is extremely important in the field of cardiovascular medicine. At the same time, it is equally important to understand the strengths and limitations of any RCT, and internal variability is a concept in clinical trials that is poorly understood. Variability in a clinical trial may be introduced at an individual level or during measurement, sampling, or conduct of the trial. It is not the same as internal validity, which is a broader concept of accuracy; to be valid, a study should minimise variability and have sound methodology. There are various steps that may be followed to minimise the internal variability in a clinical trial. One aspect of great importance is the adjudication process, which should be done meticulously and is often a step that is overlooked. It is important to standardise each step as much as possible, to ensure consistency and reduce noise at all levels. The concepts discussed in this review may serve as a roadmap to limit the influence of internal variability and maximise internal validity of RCT results.

Using real world data to support regulatory approval of drugs in rare diseases: A review of opportunities, limitations & a case example

Conducting clinical research in patients with rare diseases presents a variety of challenges. At the same time, rare diseases represent a large area of unmet medical need with a significant burden of morbidity throughout the world. One of the most common issues with designing clinical trials for rare disease populations is that the gold-standard randomized controlled trial design is often not feasible in these small and usually geographically dispersed populations. Real world data therefore has particular relevance in the rare disease setting, where it may be used as a comparator for single-arm treatment trials and in support of submissions to regulatory agencies for drugs to treat these conditions. In this report, we review the potential utility and limitations of external controls for regulatory approval of drugs in rare diseases and present a recent case example of the successful utilization of external controls in the Neurofibromatosis type 1 (NF1) population.

Interventions to improve physical activity in colorectal cancer survivors: protocol for a systematic review and meta-analysis of randomized controlled trials

AIM

To examine the effectiveness of physical activity (PA) interventions on changes in PA among colorectal cancer survivors, including an examination of theoretical versus atheoretical-driven approaches, with a special focus on their effectiveness across ethnic and racial minorities.

DESIGN

Systematic review with aggregated data meta-analyses.

DATA SOURCES

Using six databases (Cochrane Central Register of Controlled Trials, PubMed, PsycINFO, CINAHL with full text, Scopus and Web of Science), we will screen for randomized controlled trials written in English from May 1, 1993 up to December 31, 2020.

REVIEW METHODS

Dual study-selection and data abstraction will be performed. The Behavior Change Technique Taxonomy (v1) will be used to examine behavior change techniques among selected studies, while the Theory Coding Scheme will be used to assess the extent of theory use. Risk of bias will be assessed using the revised Cochrane risk-of-bias tool for randomized trials, while the strength of the evidence will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation instrument. In addition, intervention delivery will be appraised using the Template for Intervention Description and Replication. Changes in PA from each study will be calculated using the standardized mean difference effect size (Hedge's g). Results will be pooled using the inverse-variance heterogeneity model. Heterogeneity (Cochran's Q) and inconsistency (I² ) will be examined, while small-study effects (publication bias) will be evaluated using the Doi plot and LFK Index. Meta-regression will also be conducted to examine for potential associations between changes in physical activity and selected covariates (theoretical versus atheoretical-driven approaches, race/ethnicity).

DISCUSSION

This systematic review will identify specific racial/ethnic minorities for whom interventions are most effective and summarize the evidence of the effectiveness of theoretical vs. theoretical based intervention.

IMPACT

This systematic review can direct policymakers and practitioners towards actions that are likely to bring about positive physical activity behaviour change.

The use of external controls: To what extent can it currently be recommended?

With more and better clinical data being captured outside of clinical studies and greater data sharing of clinical studies, external controls may become a more attractive alternative to randomized clinical trials (RCTs). Both industry and regulators recognize that in situations where a randomized study cannot be performed, external controls can provide the needed contextualization to allow a better interpretation of studies without a randomized control. It is also agreed that external controls will not fully replace RCTs as the gold standard for formal proof of efficacy in drug development and the yardstick of clinical research. However, it remains unclear in which situations conclusions about efficacy and a positive benefit/risk can reliably be based on the use of an external control. This paper will provide an overview on types of external control, their applications and the different sources of bias their use may incur, and discuss potential mitigation steps. It will also give recommendations on how the use of external controls can be justified.

Does observational study on the effectiveness of the Twin Blocks overestimate or underestimate the results? A comparative analysis of retrospective samples versus randomized controlled trial

BACKGROUND AND OBJECTIVES

Class II malocclusion is one of the most common orthodontic problems. The Twin Block appliance has proven to be the most popular appliance for the correction of these malocclusions. Although randomized controlled trials (RCTs) on the Twin Block appliance have reported the changes to be mainly dentoalveolar, several nonrandomized studies have reported a significant skeletal improvement in these patients. Hence, the aim of this study was to compare the effectiveness of Twin Block appliance evaluated using an RCT or retrospectively selected cases (RSC) for the treatment of Class II Division 1 malocclusion in an adolescent population.

METHODS

This was a retrospective study. The results for an RCT were selected from a UK Class II multicenter study. Sixty-three patients from the trial were included. This group was matched with retrospectively selected Class II cases treated with a Twin Block functional appliance and their results submitted for Membership in Orthodontics examination in the United Kingdom, from four centers. The primary outcome was skeletal measurement ANB (A point, nasion, B point). Secondary outcomes included final peer assessment rating (PAR) scores and final overjet. Intrarater reliability of measurements was assessed. Independent samples t-test was carried out to look at the difference between the groups.

RESULTS

The reliability assessment showed excellent agreement for all measurements. The data were normally distributed. There was a statistically significant difference favoring the RSC group for final overjet (mean difference [MD] = 1.068, 95% confidence interval [CI] -0.67 to 1.47, P = 0.000) and final PAR (MD = 4.0, 95% CI -0.79 to 5.5, P = 0.000). There was no significant difference in the scores for final ANB (MD = 0.34, 95% CI -0.39 to 1.07, P = 0.33).

CONCLUSION

The RSCs show significantly improved overjet and PAR scores at the end of treatment and no statistically significant difference for skeletal change. The study raises the question of a potential role of observational studies in evaluating the effect of an intervention in orthodontics.

Testing Meldonium: Assessing Soviet pragmatic alternatives to the randomized controlled trial

BACKGROUND/AIMS

Current research largely tends to ignore the drug-testing model that was developed in the "Second World" as an explicit alternative to the randomized controlled trial. This system can be described as "socialist pharmapolitics," accounting for the specific features of state socialism that influenced the development and testing of experimental drugs. The clinical trials model employed in the "Second World" was heavily influenced by the Soviet Union, which was by far the most influential player in the socialist bloc during the Cold War. Based on extensive archival research, this article presents an empirical case of a late Soviet clinical trial as a pragmatic alternative to the randomized controlled trial model. It accounts for the divergences between the official model prescribed by the Soviet authorities and the messy realities of healthcare practice. It further outlines different factors that ultimately shaped how clinical trials were organized in Soviet institutions "on the ground." Accordingly, this article presents a "real-life" history of "socialist pharmapolitics" and outlines the problems that this system faced in practice.

METHODS

Archival research was conducted at the Russian State Archive of Scientific and Technical Documentation in Moscow. Archival files include scientific, technical, and registration documentation such as biochemical, pharmacological, and clinical descriptions of the experimental drug Meldonium, letters between various hospitals, research institutes and the Soviet regulatory body, as well as 26 reports of completed clinical trials. Manual content analysis was used for the interpretation of results.

RESULTS

This article presents an empirical case of a late Soviet clinical trial as a pragmatic alternative to the randomized controlled trial model. It demonstrates some key differences from the randomized controlled trial model. This article also highlights some of the discrepancies between the model that was officially prescribed by the Soviet authorities and the realities of experimental drug testing in the Soviet Union in the late 1980s and early 1990s. In particular, it notes some elements of randomization, double-blinding, and the use of placebo that were present in Meldonium trials despite being formally denounced by Soviet bioethics.

CONCLUSION

The Soviet model for testing experimental drugs differed from the Western one substantially in a number of respects. This difference was not only proclaimed officially by the Soviet authorities, but was for the most part enforced in clinical trials in practice. At the same time, our research demonstrates that there were important differences between the official model and the clinical realities on the ground.

Real-world evidence to support regulatory decision making: New or expanded medical product indications

There is increasing interest in utilizing real-world data (RWD) to produce real-world evidence (RWE) on the benefits and risks of medical products that could support regulatory approval decisions. The field of pharmacoepidemiology has a long history of focusing on data and evidence that would now be termed "real-world," including evidence from healthcare claims, registries, and electronic health records. However, several emerging trends over the past decade are converging to support the use of these and other RWD sources for approval decisions, and there are several recent examples and ongoing research that demonstrate how RWE may be used to support regulatory approval of new or expanded indications. The goal of this article is to review the current landscape and future directions of the use of RWE in this context. This manuscript is endorsed by the International Society for Pharmacoepidemiology (ISPE).

The dangers of ignoring underlying trends in before-and-after studies - A cautionary tale using hip fracture mortality data

BACKGROUND

Before-and-after studies are a valuable study design in situations where randomization is not feasible. These studies measure an outcome both before and after an intervention and compare the outcome rates in both time periods to determine the effectiveness of the intervention. Before-and-after studies do not involve a contemporaneous control group and must, therefore, take into account any underlying secular trends to separate the effect of the intervention from any pre-existing trend.

METHODS

To illustrate the importance of accounting for underlying trends, we performed a before-and-after study assessing 30-day mortality in hip fracture patients without any actual intervention, and instead designated an arbitrarily chosen time point as our 'intervention'. We then analysed the data first disregarding and then incorporating the pre-existing underlying trend. We did this to show that even intervention of nothing may be spuriously interpreted to have an effect if the before-and-after study design is incorrectly analysed. Our study involved a secondary analysis of routinely collected data on 30-day mortality following hip fracture in our institution.

RESULTS

We found a secular trend in our data showing improving 30-day mortality in hip fracture patients in our institution. We then demonstrated that disregarding this underlying trend showed that our intervention of nothing 'resulted' in a significant 54% decrease in mortality, from 6.7% in the 'before' period to 3.1% in the 'after' period (p < 0.0008). Though the 30-day mortality rate decreased during the 'after' period, the decrease was not significantly different from the underlying trend in the 'before' period, projected onto the 'after' period. When we accounted for the underlying trend in our analysis, the impact of the intervention (nothing) on 30-day mortality was no longer apparent (incidence rate ratio 0.75, 95% confidence interval 0.32-1.78; p = 0.5).

CONCLUSION

Our study highlights the importance of appropriate measurement and consideration of underlying trends when analysing data from before-and-after studies and illustrates what can happen should researchers neglect this important step.

AUCs and 123s: a critical appraisal of vancomycin therapeutic drug monitoring in paediatrics

The revised vancomycin guidelines recommend implementing AUC24-based therapeutic drug monitoring (TDM) using Bayesian methods in both adults and paediatrics. The motivation for this change was accumulating evidence showing aggressive dosing to achieve high troughs, as recommended in the first guidelines for adults and extrapolated to paediatrics, is associated with increased nephrotoxicity without improving clinical outcomes. AUC24-based TDM requires substantial resources that may need to be diverted from other valuable interventions. It can therefore be justified only after certain assumptions are shown to be true: (i) there is a clear relationship between vancomycin efficacy and/or toxicity and the proposed therapeutic range; and (ii) maintaining exposure within the target range with AUC24-based TDM improves clinical outcomes and/or decreases toxicity. In this review, we critically appraise the scientific basis for these assumptions. We find studies evaluating the relationship between vancomycin AUC24/MIC and efficacy in adults and children do not offer strong support for the recommended lower limit of the proposed therapeutic range (i.e. AUC24/MIC ≥400). Nephrotoxicity in children increases in a stepwise manner along the vancomycin exposure continuum but it is unclear if one parameter (AUC24 versus trough) is a superior predictor. Overall, evidence in children suggests good-to-excellent correlation between AUC24 and trough. Most importantly, there is no convincing evidence that the method of vancomycin TDM has a causal role in improving efficacy or reducing toxicity. These findings question the need to transition to resource-intensive AUC24-based TDM over retaining trough-based TDM with lower targets to minimize nephrotoxicity in paediatrics.

The Impact of Matching to Psychotherapy Preference on Engagement in a Randomized Controlled Trial for Patients With Advanced Cancer

Objective: This study examined whether patients who were randomly assigned to their preferred therapy arm had stronger engagement with their treatment than those who were randomly assigned to a non-preferred therapy arm. Method: Data were drawn from a RCT comparing Individual Meaning-Centered Psychotherapy (IMCP), with Individual Supportive Psychotherapy (ISP), in patients with advanced cancer. Treatment engagement was operationalized as patients' perceptions of the therapeutic alliance with their therapist and therapy sessions attended. Two 2 by 2 Analysis of Variance (ANOVA) models were used, with treatment preference (IMCP vs. ISP) and treatment assignment (IMCP vs. ISP) as the independent variables and working alliance and number of sessions attended as outcome variables. Results: Patients who preferred and were assigned to IMCP reported a significantly stronger alliance than those who preferred IMCP but were assigned to ISP. Conclusions: The findings from this study have broader implications for research on psychotherapy beyond the appeal of IMCP in advanced cancer patients. Patients who prefer a novel psychotherapy that they cannot engage in elsewhere, but receive the standard treatment may experience weaker alliance than patients who prefer the standard but receive the novel therapy. Trial registration: Clinicaltrial.gov ID: NCT01323309.

The case for ‘conservative pharmacotherapy’

In the modern era of rapid advances in the field of antimicrobial ‘precision dosing’ through therapeutic drug monitoring (TDM), there is growing pressure to adopt new technologies and expand the number of antimicrobials managed with TDM and/or the complexity of TDM methods. For many clinicians, it may seem inevitable that TDM must improve patient outcomes. However, based on the evidence to date, this concept remains largely a hypothesis. Conversely, it is plausible that focusing on TDM may distract from careful clinical monitoring of the patient for efficacy and drug-related toxicities and shift finite resources from other valuable interventions. In this article we make the case for embracing critical appraisal of precision dosing, remaining skeptical until persuaded by compelling evidence, and adopting new technologies only when they have proven their value over competing priorities; that is, we make the case for using ‘conservative pharmacotherapy’.

The Influence of Omega-3 Long-Chain Polyunsaturated Fatty Acid, Docosahexaenoic Acid, on Child Behavioral Functioning: A Review of Randomized Controlled Trials of DHA Supplementation in Pregnancy, the Neonatal Period and Infancy

This is a review of randomized controlled trials using docosahexaenoic acid (DHA) interventions in the first 1000 days of life with assessments of behavioral functioning in childhood. Electronic databases were searched for trials with a DHA intervention (compared with a placebo group that received no or less DHA) at any time to either women or infants during the first 1000 days, with a subsequent assessment of child behavior. There were 25 trials involving 10,320 mother-child pairs, and 71 assessments of behavior in 6867 of the children (66.5% of those originally enrolled). From the 71 assessments administered, there were 401 comparisons between a DHA group and a control group, with most reporting a null effect. There were no findings of a positive effect of DHA, and 23 instances where the DHA group had worse scores compared with the control group. There was limited evidence that DHA supplementation had any effect on behavioral development, although two of the largest trials with behavioral measures detected adverse effects. Future trials, and future follow-ups of existing trials, should make an effort to evaluate the effect of DHA intervention on behavioral functioning.

Virtual controls as an alternative to randomized controlled trials for assessing efficacy of interventions

Randomized controlled trials are ubiquitously spoken of as the "gold standard" for testing interventions and establishing causal relations. This article presents evidence for two premises. First: there are often major problems with randomized designs; it is by no means true that the only good design is a randomized design. Second: the method of virtual controls in some circumstances can and should replace randomized designs.Randomized trials can present problems with external validity or generalizability; they can be unethical; they typically involve much time, effort, and expense; their assignments to treatment conditions often can be maintained only for limited time periods; examination of their track record reveals problems with reproducibility on the one hand, and lack of overwhelming superiority to observational methods on the other hand.The method of virtual controls involves ongoing efforts to refine statistical models for prediction of outcomes from measurable variables, under conditions of no treatment or current standard of care. Research participants then join a single-arm study of a new intervention. Each participant's data, together with the formulas previously generated, predict that participant's outcome without the new intervention. These outcomes are the "virtual controls." The actual outcomes with intervention are compared with the virtual control outcomes to estimate effect sizes. Part of the research product is the prediction equations themselves, so that in clinical practice, individual treatment decisions may be aided by quantitative answers to the questions, "What is estimated to happen to this particular patient with and without this treatment?"The method of virtual controls is especially indicated when rapid results are of high priority, when withholding intervention is likely harmful, when adequate data exist for prediction of untreated or standard of care outcomes, when we want to let people choose the treatment they prefer, when tailoring treatment decisions to individuals is desirable, and when real-world clinical information can be harnessed for analysis.

The effects of resistant starches on inflammatory bowel disease in preclinical and clinical settings: a systematic review and meta-analysis

Background

Inflammatory bowel disease (IBD) is a debilitating chronic disease with limited treatment options. Resistant starches may represent a novel treatment for IBD. However, its efficacy and safety remain unclear. Our objective was to perform a systematic review to summarize the preclinical and clinical effects of resistant starch, which may help guide future studies.

Methods

Medline, EMBASE, and the Cochrane Central Register were searched. Included studies investigated the use of resistant starch therapy in in vivo animal models of IBD or human patients with IBD. Articles were screened, and data extracted, independently and in duplicate. The primary outcomes were clinical remission (clinical) and bowel mucosal damage (preclinical).

Results

21 preclinical (n = 989 animals) and seven clinical (n = 164 patients) studies met eligibility. Preclinically, resistant starch was associated with a significant reduction in bowel mucosal damage compared to placebo (standardized mean difference − 1.83, 95% CI − 2.45 to − 1.20). Clinically, five studies reported data on clinical remission but clinical and methodological heterogeneity precluded pooling. In all five, a positive effect was seen in patients who consumed resistant starch supplemented diets. The majority of studies in both the preclinical and clinical settings were at a high or unclear risk of bias due to poor methodological reporting.

Conclusions

Our review demonstrates that resistant starch is associated with reduced histology damage in animal studies, and improvements in clinical remission in IBD patients. These results need to be tempered by the risk of bias of included studies. Rigorously designed preclinical and clinical studies are warranted.

Trial registration

The review protocols were registered on PROSPERO (preclinical: CRD42019130896; clinical: CRD42019129513).

A unified framework for bias assessment in clinical research

Methodological flaws, limitations, and inadequate practices in research are well known and pose threats to the internal validity of any research study. However, there are ways of safeguarding research conduct to reduce the chance of research producing distorted results. Numerous tools now exist to assess the incorporation of such safeguards into primary research studies (also known as quality and/or risk-of-bias assessment). These tools typically include a variety of items that are then checked against those implemented in the study. Despite a lot of research in this area, no comprehensive generic classification of safeguards across study designs exist, although attempts have been made to clarify aspects of this. We review the developments in this area as well as use preliminary data from 100 methodological studies to illustrate our proposed approach. We conclude by proposing a new framework for identifying research studies at risk of being biased and the information in this article will promote a unification of the diverse approaches to facilitating bias assessment in clinical research.

Effect of a split-flow physician in triage model on abdominal CT ordering rate and yield

OBJECTIVE

The objective of this study was to compare the rate and clinical yield of computed tomography (CT) imaging between patients presenting with abdominal pain initially seen by a physician in triage (PIT) versus those seen only by physicians working in the main emergency department (ED).

METHODS

A retrospective study was conducted of all self-arrivals >18 years old presenting to a single ED with abdominal pain. Nine-hundred patients were randomly selected from both the PIT and traditional patient flow groups and rates and yields of CT imaging were compared, both alone and in a model controlling for potential confounders. Predetermined criteria for CT significance included need for admission, consult, or targeted medications.

RESULTS

The overall rate of CT imaging (unadjusted) did not differ between the PIT and traditional groups, 48.7% (95% CI 45.4-51.9) vs. 45.1% (95% CI 41.8-48.4), respectively (p = .13). The CT yield for patients seen in in the PIT group was also similar to that of the traditional group: 49.1% (95% CI 44.4-53.8) vs. 50.5% (95% CI 45.6-55.4) (p = .68). In the logistic regression model, when controlling for age, gender, ESI-acuity, race and insurance payor, PIT vs. traditional was not a predictor of CT ordering (OR 1.14, 95% CI 0.94-1.38).

CONCLUSIONS

For patients with abdominal pain, we found no significant differences in rates of CT ordering or CT yield for patients seen in a PIT vs. traditional models, suggesting the increased efficiencies offered by PIT models do not come at the cost of increased or decreased imaging utilization.

Summarising salient information on historical controls: A structured assessment of validity and comparability across studies

BACKGROUND

While placebo-controlled randomised controlled trials remain the standard way to evaluate drugs for efficacy, historical data are used extensively across the development cycle. This ranges from supplementing contemporary data to increase the power of trials to cross-trial comparisons in estimating comparative efficacy. In many cases, these approaches are performed without in-depth review of the context of data, which may lead to bias and incorrect conclusions.

METHODS

We discuss the original 'Pocock' criteria for the use of historical data and how the use of historical data has evolved over time. Based on these factors and personal experience, we created a series of questions that may be asked of historical data, prior to their use. Based on the answers to these questions, various statistical approaches are recommended. The strategy is illustrated with a case study in colorectal cancer.

RESULTS

A number of areas need to be considered with historical data, which we split into three categories: outcome measurement, study/patient characteristics (including setting and inclusion/exclusion criteria), and disease process/intervention effects. Each of these areas may introduce issues if not appropriately handled, while some may preclude the use of historical data entirely. We present a tool (in the form of a table) for highlighting any such issues. Application of the tool to a colorectal cancer data set demonstrates under what conditions historical data could be used and what the limitations of such an analysis would be.

CONCLUSION

Historical data can be a powerful tool to augment or compare with contemporary trial data, though caution is required. We present some of the issues that may be considered when involving historical data and what (if any) statistical approaches may account for differences between studies. We recommend that, where historical data are to be used in analyses, potential differences between studies are addressed explicitly.