Stratification by quality induced selection bias in a meta-analysis of clinical trials

Harm effects in non-registered versus registered randomized controlled trials of medications: a retrospective cohort study of clinical trials

BACKGROUND

Trial registration aims to address potential bias from selective or non-reporting of findings, and therefore has a vital role in promoting transparency and accountability of clinical research. In this study, we aim to investigate the influence of trial registration on estimated harm effects in randomized controlled trials of medication interventions.

METHODS

We searched PubMed for systematic reviews and meta-analyses of randomized trials on medication harms indexed between January 1, 2015, and January 1, 2020. To be included in the analyses, eligible meta-analyses should have at least five randomized trials with distinct registration statuses (i.e., prospectively registered, retrospectively registered, and non-registered) and 2 by 2 table data for adverse events for each trial. To control for potential confounding, trials in each meta-analysis were analyzed within confounder-harmonized groups (e.g., dosage) identified using the Directed Acyclic Graph method. The harm estimates arising from the trials with different registration statuses were compared within the confounder-harmonized groups using hierarchical linear regression. Results are shown as ratio of odds ratio (OR) and 95% confidence interval (CI).

RESULTS

The dataset consists of 629 meta-analyses of harms with 10,069 trials. Of these trials, 74.3% were registered, and 23.9% were not registered, and for those registered, 70.6% were prospectively registered, while 26.3% were retrospectively registered. In comparison to prospectively registered trials, both non-registered trials (ratio of OR = 0.82, 95%CI 0.68 to 0.98, P = 0.03) and retrospectively registered trials (ratio of OR = 0.75, 95%CI 0.66 to 0.86, P < 0.01) had lower OR for harms based on 69 and 126 confounders-harmonized groups. The OR of harms did not differ between retrospectively registered and non-registered trials (ratio of OR = 1.02, 95%CI 0.85 to 1.23, P = 0.83) based on 76 confounders-harmonized groups.

CONCLUSIONS

Medication-related harms may be understated in non-registered trials, and there was no obvious evidence that retrospective registration had a demonstrable benefit in reducing such selective or absent reporting. Prospective registration is highly recommended for future trials.

Comparative efficacy and choice of lipid-lowering drugs for cardiovascular and kidney outcomes in patients with chronic kidney disease: A systematic review and network meta-analysis

BACKGROUND

The effect of exact classes of lipid-lowering drugs (LLDs) on preventing major adverse cardiovascular events (MACEs) and poor renal outcomes is not well characterized in the chronic kidney disease (CKD) population.

METHODS

We performed a frequentist random-effects network meta-analysis of randomized controlled trials (RCTs) to evaluate the protective effect of the LLDs in non-dialysis CKD patients. The PubMed, Embase, Web of Science, and Cochrane Library databases were systematically searched for relevant trials published before March 31, 2024. The primary outcome was the incidence of MACEs. The secondary outcomes comprised all-cause mortality, end-stage kidney disease, changes in estimated glomerular filtration rate (eGFR) and proteinuria, and safety.

RESULTS

Forty-nine eligible RCTs with 77,826 participants with non-dialysis CKD were included. With moderate confidence in the evidence, rosuvastatin and atorvastatin showed statistically significantly more efficacy in reducing the risk of MACE, with a pooled risk ratio of 0.55 (95% CI 0.33-0.91) for rosuvastatin and 0.67 (0.49-0.90) for atorvastatin, respectively, compared with the control group. For the change in the eGFR, atorvastatin (mean difference [MD], 1.40; 95% CI, 0.61 to 2.18), rosuvastatin (MD, 1.73; 95% CI, 0.63 to 2.83), and statin plus ezetimibe (MD, 2.35; 95% CI, 0.44 to 4.26) showed statistically significant increases in the mean eGFR.

CONCLUSION

In patients with non-dialysis CKD, there is sufficient evidence to show that rosuvastatin and atorvastatin were statistically significantly more effective and preferable in reducing the risk of MACE and increasing the mean eGFR compared with the control group.

The effect of unpredictability on the perception of pain: a systematic review and meta-analysis

ABSTRACT

Despite being widely assumed, the worsening impact of unpredictability on pain perception remains unclear because of conflicting empirical evidence, and a lack of systematic integration of past research findings. To fill this gap, we conducted a systematic review and meta-analysis focusing on the effect of unpredictability on pain perception. We also conducted meta-regression analyses to examine the moderating effect of several moderators associated with pain and unpredictability: stimulus duration, calibrated stimulus pain intensity, pain intensity expectation, controllability, anticipation delay, state and trait negative affectivity, sex/gender and age of the participants, type of unpredictability (intensity, onset, duration, location), and method of pain induction (thermal, electrical, mechanical pressure, mechanical distention). We included 73 experimental studies with adult volunteers manipulating the (un)predictability of painful stimuli and measuring perceived pain intensity and pain unpleasantness in predictable and unpredictable contexts. Because there are insufficient studies with patients, we focused on healthy volunteers. Our results did not reveal any effect of unpredictability on pain perception. However, several significant moderators were found, ie, targeted stimulus pain intensity, expected pain intensity, and state negative affectivity. Trait negative affectivity and uncontrollability showed no significant effect, presumably because of the low number of included studies. Thus, further investigation is necessary to clearly determine their role in unpredictable pain perception.

Depressive Symptoms Among Higher Education Students in Germany-A Systematic Review and Meta-Analysis

Objectives

Higher education students in Germany are vulnerable to depressive symptoms. Despite ample evidence, no comprehensive review has recently been conducted. Thus, our systematic review and meta-analysis aims at describing the extent to which students are affected by depressive symptoms.

Methods

We searched three databases for articles reporting the prevalence rates of depressiveness among students in Germany published between 2002 and 2023. Pooled prevalence rates were calculated using random effects models, both for the overall sample and for subgroups categorized by gender, study setting, assessment instrument, and whether the study was conducted before or during the COVID-19 pandemic.

Results

The search yielded 992 records. After screening, 60 articles remained for data extraction. About one out of five students (21.1%) exhibits depressive symptoms. Pooled prevalence rates differ between subgroups, with higher rates during the COVID-19 pandemic than before (30.6% versus 18.0%) and with females being more affected than their male counterparts (29.0% versus 23.1%).

Conclusion

This review underlines the urgency with which the mental health of students should be addressed at the (higher educational) policy level.

Clinical Trial Registration: PROPSPERO, Identifier CRD42022384066.

Sensorimotor tests in patients with neck pain and its associated disorders: a systematic review and meta-analysis

This systematic review aimed to synthesize the current evidence regarding neck sensorimotor testing in individuals with neck pain, assess the differences between neck pain groups and healthy controls, and recognize factors that might affect test results. We performed the data search using PubMed, Embase, PsycINFO, CINAHL, and Scopus databases. We used a two-step screening process to identify studies. Furthermore, we screened the reference lists for additional studies. Hedges g was used to present the difference between neck pain groups and asymptomatic individuals. We assessed the quality of the studies using the QUADAS tool. The final review included 34 studies, of which 25 were related to the joint position error test, four to the smooth pursuit neck torsion test and six to the balance test. Our meta-analysis showed poorer joint-position sense, oculomotor function, and wider postural sway in individuals with neck pain than healthy controls. The size of the difference between the groups seemed to be influenced by the intensity of the pain and the presence of dizziness. Therefore, it might be helpful in future studies to differentiate patients with neck pain into subgroups based on their symptom and demographic profiles to assess other factors that significantly affect cervical sensorimotor control.

Tranexamic Acid for Traumatic Injury in the Emergency Setting: A Systematic Review and Bias-Adjusted Meta-Analysis of Randomized Controlled Trials

STUDY OBJECTIVE

Traumatic injury causes a significant number of deaths due to bleeding. Tranexamic acid (TXA), an antifibrinolytic agent, can reduce bleeding in traumatic injuries and potentially enhance outcomes. Previous reviews suggested potential TXA benefits but did not consider the latest trials.

METHODS

A systematic review and bias-adjusted meta-analysis were performed to assess TXA's effectiveness in emergency traumatic injury settings by pooling estimates from randomized controlled trials. Researchers searched Medline, Embase, and Cochrane Central for randomized controlled trials comparing TXA's effects to a placebo in emergency trauma cases. The primary endpoint was 1-month mortality. The methodological quality of the trials underwent assessment using the MASTER scale, and the meta-analysis applied the quality-effects method to adjust for methodological quality.

RESULTS

Seven randomized controlled trials met the set criteria. This meta-analysis indicated an 11% decrease in the death risk at 1 month after TXA use (odds ratio [OR] 0.89, 95% confidence interval [CI] 0.84 to 0.95) with a number needed to treat of 61 to avoid 1 additional death. The meta-analysis also revealed reduced 24-hour mortality (OR 0.76, 95% CI 0.65 to 0.88) for TXA. No compelling evidence of increased vascular occlusive events emerged (OR 0.96, 95% CI 0.73 to 1.27). Subgroup analyses highlighted TXA's effectiveness in general trauma versus traumatic brain injury and survival advantages when administered out-of-hospital versus inhospital.

CONCLUSIONS

This synthesis demonstrates that TXA use for trauma in emergencies leads to a reduction in 1-month mortality, with no significant evidence of problematic vascular occlusive events. Administering TXA in the out-of-hospital setting is associated with reduced mortality compared to inhospital administration, and less mortality with TXA in systemic trauma is noted compared with traumatic brain injury specifically.

Interventions to reduce Salmonella and Campylobacter during chilling and post-chilling stages of poultry processing: a systematic review and meta-analysis

Salmonella and Campylobacter are common bacterial hazards causing foodborne illnesses worldwide. A large proportion of Salmonella and Campylobacter illnesses are attributed to contaminated poultry products that are mishandled or under cooked. Processing interventions such as chilling and post-chill dip are critical to reducing microbial contamination of poultry. A comprehensive search of the literature published between 2000 and 2021 was conducted in the databases Web of Science, Academic Search Complete, and Academic OneFile. Studies were included if they were in English and investigated the effects of interventions against Salmonella and/or Campylobacter on whole carcasses and/or parts during the chilling or post-chill stages of poultry processing. Random-effects meta-analyses were performed using the "meta" package in the R programming language. Subgroup analyses were assessed according to outcome measure reported, microorganism tested, processing stage assessed, and chemical treatment used. The results included 41 eligible studies. Eighteen studies reported results of 28 separate interventions against Salmonella and 31 reported results of 50 separate interventions against Campylobacter. No significant difference (P> 0.05) was observed when comparing the combined mean difference of all interventions targeting Salmonella to the combined mean difference of all interventions targeting Campylobacter or when comparing chilling times within each pathogen subgroup. For analyses examining antimicrobial additives, peroxyacetic acid (PAA) had the largest reduction against Salmonella population regardless of chilling time (P< 0.05). PAA also had the largest reduction against Campylobacter population and prevalence during primary chilling (P< 0.01). Air chilling showed a lower reduction for Campylobacter than any immersion chilling intervention (P< 0.05). Chilling time and antimicrobial used during poultry processing had varying effects depending on the pathogen and outcome measure investigated (concentration or prevalence). High heterogeneity and low sample numbers in most analyses suggest that more high-quality research that is well-designed and has transparent reporting of methodology and results is needed to corroborate the results.

The revised JBI critical appraisal tool for the assessment of risk of bias for quasi-experimental studies

Systematic reviews of effectiveness offer a rigorous synthesis of the best evidence available regarding the effects of interventions or treatments. Randomized controlled trials are considered the optimal study design for evaluating the effectiveness of interventions and are the ideal study design for inclusion in a systematic review of effectiveness. In the absence of randomized controlled trials, quasi-experimental studies may be relied on to provide information on treatment or intervention effectiveness. However, such studies are subject to unique considerations regarding their internal validity and, consequently, the assessment of the risk of bias of these studies needs to consider these features of design and conduct. The JBI Effectiveness Methodology Group has recently commenced updating the suite of JBI critical appraisal tools for quantitative study designs to align with the latest advancements in risk of bias assessment. This paper presents the revised critical appraisal tool for risk of bias assessment of quasi-experimental studies; offers practical guidance for its use; provides examples for interpreting the results of risk of bias assessment; and discusses major changes from the previous version, along with the justifications for those changes.

Comparison of bias adjustment in meta-analysis using data-based and opinion-based methods

INTRODUCTION

Several methods exist for bias adjustment of meta-analysis results, but there has been no comprehensive comparison with unadjusted methods. We compare 6 bias-adjustment methods with 2 unadjusted methods to examine how these different methods perform.

METHODS

We re-analyzed a meta-analysis that included 10 randomized controlled trials. Two data-based methods (Welton's data-based approach and Doi's quality effects model) and 4 opinion-informed methods (opinion-based approach, opinion-based distributions combined statistically with data-based distributions, numerical opinions informed by data-based distributions, and opinions obtained by selecting areas from data-based distributions) were used to incorporate methodological quality information into the meta-analytical estimates. The results of these 6 methods were compared with 2 unadjusted models: the DerSimonian-Laird random effects model and Doi's inverse variance heterogeneity model.

RESULTS

The 4 opinion-based methods returned the random effects model estimates with wider uncertainty. The data-based and quality effects methods returned different results and aligned with the inverse variance heterogeneity method with some minor downward bias adjustment.

CONCLUSION

Opinion-based methods seem to only add uncertainty rather than bias adjust.

PROTOCOL: Impact of summer programmes on the outcomes of disadvantaged or at risk young people: A systematic review

This is the protocol for a Campbell systematic review. The objectives are as follows: based on the findings of the initial literature review regarding the types of summer programmes used to support disadvantaged or at risk young people, the outcomes they aim to affect and the goals of the funding organisations and research team, this review will seek to answer the following research questions: (1) to what extent does participation in summer employment programmes improve outcomes for disadvantaged or at risk young people, (2) to what extent does participation in summer educational programmes improve outcomes for disadvantaged or at risk young people, and (3) to what extent do the impacts of summer programmes vary based on the study, participant and intervention characteristics including the racial and ethnic make-up of participants?

Effective inclusion practices for neurodiverse children and adolescents in informal STEM learning: a systematic review protocol

BACKGROUND

Informal learning experiences in science, technology, engineering, and math (STEM) can enhance STEM learning that occurs in formal educational settings and curricula as well as generate enthusiasm for considering STEM careers. The aim of this systematic review is to focus on the experiences of neurodiverse students in informal STEM learning. Neurodiversity is a subgroup of neurodevelopmental conditions, such as autism, attention deficit disorder, dyslexia, dyspraxia, and other neurological conditions. The neurodiversity movement regards these conditions as natural forms of human variation, as opposed to dysfunction, and recognizes that neurodiverse individuals possess many strengths relevant to STEM fields.

METHODS

The authors will systematically search electronic databases for relevant research and evaluation articles addressing informal STEM learning for K-12 children and youth with neurodiverse conditions. Seven databases and content-relevant websites (e.g., informalscience.org) will be searched using a predetermined search strategy and retrieved articles will be screened by two members of the research team. Data synthesis will include meta-synthesis techniques, depending on the designs of the studies.

DISCUSSION

The synthesis of the findings resulting from various research and evaluation designs, across the K-12 age span, and across various informal STEM learning contexts, will lead to depth and breadth of understanding of ways to improve informal STEM learning programs for neurodiverse children and youth. The identification of informal STEM learning program components and contexts shown to yield positive results will provide specific recommendations for improving inclusiveness, accessibility, and STEM learning for neurodiverse children and youth.

TRIAL REGISTRATION

The current study has been registered in PROSPERO.

REGISTRATION NUMBER

CRD42021278618.

The Psychological Impact of Restorative Justice Practices on Victims of Crimes-a Systematic Review

BACKGROUND

Restorative justice emerges as a theoretical-practical approach to the criminal legal system, in which the reparation of damage of the victim is a central point. However, the growing empirical production referring to the effects of this approach on victims is sometimes shown to be weakened or dispersed, focusing mainly on their satisfaction.

OBJECTIVE

The present work intended to systematically evaluate the empirical production of the restorative justice field, to aggregate and examine information in the literature regarding the psychological impacts on victims who participated in restorative practices.

METHODS

A search was made using electronic databases to identify quantitative, qualitative, and mixed-method studies, published between January 2000 and December 2020 that reported psychological impacts on real victims of crimes, who participated in mediations/conferences victim-offender.

RESULTS

35 studies were identified as focusing on the psychological impacts on victims resulting from restorative practices. These studies have shown effects on post-traumatic symptomatology, on the emotions and emotional needs resulted from victimization, as well as on the victims' perceptions of their offenders.

CONCLUSIONS

The present research showed that restorative justice practices have a positive psychological impact on victims, who are frequently forgotten in conventional justice, and that some of these impacts persist over time.

Understanding the medication safety challenges for patients with mental illness in primary care: a scoping review

BACKGROUND

Mental illness and medication safety are key priorities for healthcare systems around the world. Despite most patients with mental illness being treated exclusively in primary care, our understanding of medication safety challenges in this setting is fragmented.

METHOD

Six electronic databases were searched between January 2000-January 2023. Google Scholar and reference lists of relevant/included studies were also screened for studies. Included studies reported data on epidemiology, aetiology, or interventions related to medication safety for patients with mental illness in primary care. Medication safety challenges were defined using the drug-related problems (DRPs) categorisation.

RESULTS

Seventy-nine studies were included with 77 (97.5%) reporting on epidemiology, 25 (31.6%) on aetiology, and 18 (22.8%) evaluated an intervention. Studies most commonly (33/79, 41.8%) originated from the United States of America (USA) with the most investigated DRP being non-adherence (62/79, 78.5%). General practice was the most common study setting (31/79, 39.2%) and patients with depression were a common focus (48/79, 60.8%). Aetiological data was presented as either causal (15/25, 60.0%) or as risk factors (10/25, 40.0%). Prescriber-related risk factors/causes were reported in 8/25 (32.0%) studies and patient-related risk factors/causes in 23/25 (92.0%) studies. Interventions to improve adherence rates (11/18, 61.1%) were the most evaluated. Specialist pharmacists provided the majority of interventions (10/18, 55.6%) with eight of these studies involving a medication review/monitoring service. All 18 interventions reported positive improvements on some medication safety outcomes but 6/18 reported little difference between groups for certain medication safety measures.

CONCLUSION

Patients with mental illness are at risk of a variety of DRPs in primary care. However, to date, available research exploring DRPs has focused attention on non-adherence and potential prescribing safety issues in older patients with dementia. Our findings highlight the need for further research on the causes of preventable medication incidents and targeted interventions to improve medication safety for patients with mental illness in primary care.

A systematic review and meta-analysis of the sources of Salmonella in poultry production (pre-harvest) and their relative contributions to the microbial risk of poultry meat

Salmonella is a major foodborne pathogen associated with poultry and poultry products and a leading cause for human salmonellosis. Salmonella is known to transmit in poultry flocks both vertically and horizontally. However, there is a lack of knowledge on relative contribution of the factors on Salmonella prevalence in poultry live production system including hatchery, feed, water, environment-interior, and -exterior. Therefore, a systematic review and meta-analysis was conducted to quantify the potential sources of Salmonella during preharvest and their relative contributions to the microbial risk of poultry meat. A total of 16,800 studies identified from Google Scholar and 37 relevant studies were included in the meta-analysis for relative contributions to Salmonella positivity on broilers after applying exclusion criteria. A generalized linear mixed model approach combined with logit transformation was used in the current study to stabilize the variance. The analysis revealed that the hatchery is the most significant contributor of Salmonella with a prevalence of 48.5%. Litter, feces, and poultry house internal environment were the other 3 major contributing factors with a prevalence of 25.4, 16.3, and 7.9%, respectively. Moreover, poultry house external environment (4.7%), feed (4.8%), chicks (4.7%), and drinker water also contributed to the Salmonella positivity. Results from this meta-analysis informed the urgent need for controls in live production to further reduce Salmonella in fresh, processed poultry. The control strategies can include eliminating the sources of Salmonella and incorporating interventions in live production to reduce Salmonella concentrations in broilers.

Quality assessment of systematic reviews with meta-analysis in undergraduate nursing education

BACKGROUND

Little attention has been given to the methodological quality of meta-analyses in nursing education. This warrants further improvements in meta-analyses in nursing education.

OBJECTIVE

This study aimed to assess the methodological quality of meta-analysis in the field of undergraduate nursing education.

DESIGN

This was a methodological study to review the methodological quality of systematic reviews (SRs) with meta-analysis.

METHODS

Exhaustive literature searches were performed using five comprehensive databases. Between 1994 and 2022, 11,827 studies were identified, and 41 full-text articles met the inclusion criteria. Two researchers extracted data using A Measurement Tool to Assess Systematic Reviews (AMSTAR)-2. The Chi-square test was conducted to make comparisons before and after 2017, the year AMSTAR-2 was released.

RESULTS

A comprehensive literature retrieval strategy, inclusion and exclusion criteria, literature selection, and data extraction were observed in nursing education more than in other disciplines. Improvements to be made include pre-specifying the protocol, providing a list of excluded studies with their exclusion reasons, reporting the source of funding for the included studies, assessing and discussing the potential impact of risk of bias, as well as investigating and discussing publication bias and its impact.

CONCLUSIONS

The number of SRs with meta-analyses in nursing education is increasing. This warrants efforts to improve the quality of research. In addition, guidelines for reporting SRs in the field of nursing education should be constantly updated.

The Consistency between Registered Acupuncture-Moxibustion Clinical Studies and Their Published Studies and Update Status of Registered Information

BACKGROUND

Few studies have analyzed the consistency between registered acupuncture-moxibustion clinical studies and their published research results as well as their update status of registered information.

METHODS

We searched for acupuncture-moxibustion clinical studies that were registered at the World Health Organization International Clinical Trials Registry Platform between 2013 and 2015 and collected data regarding their characteristics and update status. Published results of these registered studies were identified and compared with registered information.

RESULTS

A total of 425 registered acupuncture-moxibustion clinical studies were included; 379 (89.2%) of them were interventional studies, and the remaining 46 (10.8%) were observational studies. Forty-six studies (10.8%) were found to have published results, and 51 published articles were identified. Overall, 73.2% (311) of registered studies did not update the research status in time; 46.6% (198) stopped updating before recruiting; 21.6% (92) stopped updating after recruiting; and 4.9% (21) stopped updating after completion. Regarding the 46 studies with published results, 29 (63.0%) were considered to be affected by reporting bias. These reporting biases predominantly involved the omission of some predefined outcomes or endpoints (16 studies), contradictions regarding descriptions of sample sizes (9 studies), discrepancies in treatment measurements or group distribution (7 studies), and inconsistent treatment durations (4 studies). When compared with other studies, significant and various reporting biases could also be commonly found in fields other than acupuncture-moxibustion.

CONCLUSIONS

There were many discrepancies between registered information and published reports on acupuncture-moxibustion, which could also be commonly observed in other fields. Moreover, a large proportion of registered studies did not update their research status in time. Efforts should be made to improve the reporting quality and timely updates.

Hintergrund

Es gibt nur wenige Studien, in denen die Übereinstimmung zwischen den registrierten klinischen Studien zur Akupunktur und Moxibustion mit den veröffentlichten Studienergebnissen und dem Aktualisierungsstand der Informationen im Register untersucht wurde.

Methoden

Wir suchten nach klinischen Studien zur Akupunktur und Moxibustion, die zwischen 2013 und 2015 auf der International Clinical Trials Registry Platform der Weltgesundheitsorganisation registriert wurden, und erhoben Daten zu ihren Merkmalen und ihrem Aktualisierungsstand. Die veröffentlichten Ergebnisse der registrierten Studien wurden identifiziert und mit den Informationen im Register verglichen.

Ergebnisse

Insgesamt wurden 425 registrierte klinische Studien zur Akupunktur und Moxibustion eingeschlossen, davon waren 379 (89,2 %) Interventionsstudien und die restlichen 46 (10,8 %) waren Beobachtungsstudien. Es wurden 46 Studien (10,8 %) mit veröffentlichten Ergebnissen gefunden und 51 veröffentlichte Artikel identifiziert. Insgesamt wurde bei 73,2 % (311) der registrierten Studien der Forschungsstand nicht zeitnah aktualisiert; bei 46,6 % (198) wurde die Aktualisierung vor der Rekrutierung eingestellt; bei 21,6 % (92) wurde die Aktualisierung nach der Rekrutierung eingestellt und bei 4,9 % (21) wurde die Aktualisierung nach Abschluss der Studie eingestellt. Von den 46 Studien mit veröffentlichten Ergebnissen wurden 29 (63,0 %) als von Publikationsverzerrung betroffen angesehen. Diese Publikationsverzerrung betraf vor allem die Auslassung einiger vordefinierter Zielkriterien oder Endpunkte (16 Studien), Widersprüche bei der Beschreibung des Stichprobenumfangs (9 Studien), Diskrepanzen bei den Behandlungsmessungen oder der Gruppenverteilung (7 Studien) und Inkonsistenzen bei der Behandlungsdauer (4 Studien). Beim Vergleich mit anderen Studien wurden auch in anderen Bereichen als Akupunktur und Moxibustion häufig signifikante und unterschiedliche Publikationsverzerrungen festgestellt.

Schlussfolgerungen

Es bestanden zahlreiche Diskrepanzen zwischen den Informationen im Register und den veröffentlichten Berichten über Akupunktur und Moxibustion, die auch in anderen Bereichen häufig zu beobachten waren. Darüber hinaus wurde bei einem Großteil der registrierten Studien der Forschungsstand nicht zeitnah aktualisiert. Es sollten Anstrengungen unternommen werden, um die Qualität der Berichterstattung und die zeitnahe Aktualisierung zu verbessern.

The revised JBI critical appraisal tool for the assessment of risk of bias for randomized controlled trials

JBI recently began the process of updating and revising its suite of critical appraisal tools to ensure that these tools remain compatible with recent developments within risk of bias science. Following a rigorous development process led by the JBI Effectiveness Methodology Group, this paper presents the revised critical appraisal tool for the assessment of risk of bias for randomized controlled trials. This paper also presents practical guidance on how the questions of this tool are to be interpreted and applied by systematic reviewers, while providing topical examples. We also discuss the major changes made to this tool compared to the previous version and justification for why these changes facilitate best-practice methodologies in this field.

One-Third of Systematic Reviews in Rehabilitation Applied the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) System to Evaluate Certainty of Evidence: A Meta-Research Study

OBJECTIVE

To determine how many systematic reviews (SRs) of the literature in rehabilitation assess the certainty of evidence (CoE) and how many apply the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to do this.

DATA SOURCES

For this meta-research study, we searched PubMed and Cochrane Database of Systematic Reviews databases for SRs on rehabilitation published in 2020.

STUDY SELECTION AND DATA EXTRACTION

Two reviewers independently selected the SRs and extracted the data. Reporting characteristics and appropriate use of the GRADE system were assessed.

DATA SYNTHESIS

The search retrieved 827 records: 29% (239/827) SRs evaluated CoE, 68% (163/239) of which applied the GRADE system. GRADE was used by SRs of randomized controlled trials (RCTs, 88%; 144/163), non-randomized intervention studies (NRIS, 2%; 3/163), and both RCT and NRIS (10%; 16/163). In the latter case, a separate GRADE assessment according to the study design was not provided in 75% (12/16). The reasons for GRADE judgment were reported in 82% (134/163) of SRs.

CONCLUSIONS

One-third of SRs in rehabilitation assessed CoE with the GRADE system. GRADE assessment was presented transparently by most SRs. Journal editors and funders should encourage the uptake of the GRADE system when considering SRs in rehabilitation for publication. The authors should pre-define GRADE assessment in a registered and/or published protocol.

Combining robot-assisted therapy with virtual reality or using it alone? A systematic review on health-related quality of life in neurological patients

BACKGROUND

In the field of neurorehabilitation, robot-assisted therapy (RAT) and virtual reality (VR) have so far shown promising evidence on multiple motor and functional outcomes. The related effectiveness on patients' health-related quality of life (HRQoL) has been investigated across neurological populations but still remains unclear. The present study aimed to systematically review the studies investigating the effects of RAT alone and with VR on HRQoL in patients with different neurological diseases.

METHODS

A systematic review of the studies evaluating the impact of RAT alone and combined with VR on HRQoL in patients affected by neurological diseases (i.e., stroke, multiple sclerosis, spinal cord injury, Parkinson's Disease) was conducted according to PRISMA guidelines. Electronic searches of PubMed, Web of Science, Cochrane Library, CINAHL, Embase, and PsychINFO (2000-2022) were performed. Risk of bias was evaluated through the National Institute of Health Quality Assessment Tool. Descriptive data regarding the study design, participants, intervention, rehabilitation outcomes, robotic device typology, HRQoL measures, non-motor factors concurrently investigated, and main results were extracted and meta-synthetized.

RESULTS

The searches identified 3025 studies, of which 70 met the inclusion criteria. An overall heterogeneous configuration was found regarding the study design adopted, intervention procedures and technological devices implemented, rehabilitation outcomes (i.e., related to both upper and lower limb impairment), HRQoL measures administered, and main evidence. Most of the studies reported significant effects of both RAT and RAT plus VR on patients HRQoL, whether they adopted generic or disease-specific HRQoL measures. Significant post-intervention within-group changes were mainly found across neurological populations, while fewer studies reported significant between-group comparisons, and then, mostly in patients with stroke. Longitudinal investigations were also observed (up to 36 months), but significant longitudinal effects were exclusively found in patients with stroke or multiple sclerosis. Finally, concurrent evaluations on non-motor outcomes beside HRQoL included cognitive (i.e., memory, attention, executive functions) and psychological (i.e., mood, satisfaction with the treatment, device usability, fear of falling, motivation, self-efficacy, coping, and well-being) variables.

CONCLUSIONS

Despite the heterogeneity observed among the studies included, promising evidence was found on the effectiveness of RAT and RAT plus VR on HRQoL. However, further targeted short- and long-term investigations, are strongly recommended for specific HRQoL subcomponents and neurological populations, through the adoption of defined intervention procedures and disease-specific assessment methodology.

Strategies for Enhancing the Implementation of Universal Mental Health Prevention Programs in Schools: A Systematic Review

A number of school-based mental health prevention programs have been found to be effective in research trials, but little is known about how to support implementation in real-life settings. To address this translational problem, this systematic review aims to identify effective strategies for enhancing the implementation of mental health prevention programs for children in schools. Four electronic databases were searched for empirical, peer-reviewed articles in English from January 2000 to October 2021 reporting the effects of implementation strategies for school-based universal mental health programs. Twenty-one articles were included in the narrative synthesis and assessed for quality using the Mixed Methods Appraisal Tool. Twenty-two strategies were found to be effective at improving program fidelity or adoption. The strategies with the strongest positive evidence base were those that involved monitoring and provision of feedback, engaging principals as program leaders, improving teachers' buy-in and organising school personnel implementation meetings. We recommend school-based practitioners trial strategies with positive findings from this review as part of their continuous quality improvement. This review highlights the pressing need for large-scale, randomised controlled trials to develop and trial more robust strategies to enhance adoption, as the five implementation studies found to measure adoption used qualitative methods limited by small samples sizes and case study designs.

Systematic Review and Meta-Analysis of Metabolic Syndrome and Its Components in Latino Immigrants to the USA

The Metabolic Syndrome (MetS) is an increasingly prevalent condition globally. Latino populations in the USA have shown an alarming increase in factors associated with MetS in recent years. The objective of the present systematic review was to determine the prevalence of MetS and its risk factors in immigrant Latinos in the USA and perform a meta-analysis of those prevalence. The review included cross-sectional, cohort, or case−control studies involving adult immigrant Latinos in the USA, published during the period 1980−2020 in any language. Studies involving individuals who were pregnant, aged <18 years, immigrant non-Latinos, published outside the 1980−2020 period, or with other design types were excluded. The Pubmed, Web of Science, Embase, Lilacs, Scielo, and Google Scholar databases were searched. The risk of bias was assessed using the checklists of the Joanna Briggs Institute. The review included 60 studies, and the meta-analysis encompassed 52 studies. The pooled prevalence found for hypertension, diabetes, general obesity, and abdominal obesity were 28% (95% Confidence Interval (CI): 23−33%), 17% (95% CI: 14−20%), 37% (95% CI: 33−40%), and 54% (95% CI: 48−59%), respectively. The quality of the evidence of the primary studies was classified as low or very low. Few studies including immigrants from South America were identified. Further studies of those immigrants are needed due to the cultural, dietary, and language disparities among Latin American countries. The research protocol was registered with the Open Science Framework (OSF).

The effect of occupational exposure to welding fumes on trachea, bronchus and lung cancer: A systematic review and meta-analysis from the WHO/ILO Joint Estimates of the Work-related Burden of Disease and Injury

BACKGROUND

The World Health Organization (WHO) and the International Labour Organization (ILO) are the producers of the WHO/ILO Joint Estimates of the Work-related Burden of Disease and Injury (WHO/ILO Joint Estimates). Welding fumes have been classified as carcinogenic to humans (Group 1) by the WHO International Agency for Research on Cancer (IARC) in IARC Monograph 118; this assessment found sufficient evidence from studies in humans that welding fumes are a cause of lung cancer. In this article, we present a systematic review and meta-analysis of parameters for estimating the number of deaths and disability-adjusted life years from trachea, bronchus, and lung cancer attributable to occupational exposure to welding fumes, to inform the development of WHO/ILO Joint Estimates on this burden of disease (if considered feasible).

OBJECTIVES

We aimed to systematically review and meta-analyse estimates of the effect of any (or high) occupational exposure to welding fumes, compared with no (or low) occupational exposure to welding fumes, on trachea, bronchus, and lung cancer (three outcomes: prevalence, incidence, and mortality).

DATA SOURCES

We developed and published a protocol, applying the Navigation Guide as an organizing systematic review framework where feasible. We searched electronic databases for potentially relevant records from published and unpublished studies, including Medline, EMBASE, Web of Science, CENTRAL and CISDOC. We also searched grey literature databases, Internet search engines, and organizational websites; hand-searched reference lists of previous systematic reviews; and consulted additional experts.

STUDY ELIGIBILITY AND CRITERIA

We included working-age (≥15 years) workers in the formal and informal economy in any Member State of WHO and/or ILO but excluded children (<15 years) and unpaid domestic workers. We included randomized controlled trials, cohort studies, case-control studies, and other non-randomized intervention studies with an estimate of the effect of any (or high) occupational exposure to welding fumes, compared with occupational exposure to no (or low) welding fumes, on trachea, bronchus, and lung cancer (prevalence, incidence, and mortality).

STUDY APPRAISAL AND SYNTHESIS METHODS

At least two review authors independently screened titles and abstracts against the eligibility criteria at a first review stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. If studies reported odds ratios, these were converted to risk ratios (RRs). We combined all RRs using random-effects meta-analysis. Two or more review authors assessed the risk of bias, quality of evidence, and strength of evidence, using the Navigation Guide tools and approaches adapted to this project. Subgroup (e.g., by WHO region and sex) and sensitivity analyses (e.g., studies judged to be of "high"/"probably high" risk of bias compared with "low"/"probably low" risk of bias) were conducted.

RESULTS

Forty-one records from 40 studies (29 case control studies and 11 cohort studies) met the inclusion criteria, comprising over 1,265,512 participants (≥22,761 females) in 21 countries in three WHO regions (Region of the Americas, European Region, and Western Pacific Region). The exposure and outcome were generally assessed by job title or self-report, and medical or administrative records, respectively. Across included studies, risk of bias was overall generally probably low/low, with risk judged high or probably high for several studies in the domains for misclassification bias and confounding. Our search identified no evidence on the outcome of having trachea, bronchus, and lung cancer (prevalence). Compared with no (or low) occupational exposure to welding fumes, any (or high) occupational exposure to welding fumes increased the risk of acquiring trachea, bronchus, and lung cancer (incidence) by an estimated 48 % (RR 1.48, 95 % confidence interval [CI] 1.29-1.70, 23 studies, 57,931 participants, I² 24 %; moderate quality of evidence). Compared with no (or low) occupational exposure to welding fumes, any (or high) occupational exposure to welding fumes increased the risk dying from trachea, bronchus, and lung cancer (mortality) by an estimated 27 % (RR 1.27, 95 % CI 1.04-1.56, 3 studies, 8,686 participants, I² 0 %; low quality of evidence). Our subgroup analyses found no evidence for difference by WHO region and sex. Sensitivity analyses supported the main analyses.

CONCLUSIONS

Overall, for incidence and mortality of trachea, bronchus, and lung cancer, we judged the existing body of evidence for human data as "sufficient evidence of harmfulness" and "limited evidence of harmfulness", respectively. Occupational exposure to welding fumes increased the risk of acquiring and dying from trachea, bronchus, and lung cancer. Producing estimates for the burden of trachea, bronchus, and lung cancer attributable to any (or high) occupational exposure to welding fumes appears evidence-based, and the pooled effect estimates presented in this systematic review could be used as input data for the WHO/ILO Joint Estimates. PROTOCOL IDENTIFIER: https://doi.org/10.1016/j.envint.2020.106089.

Should We Use Hyperbaric Oxygen for Carbon Monoxide Poisoning Management? A Network Meta-Analysis of Randomized Controlled Trials

Carbon monoxide (CO) poisoning is a public health issue in numerous countries. Oxygen supplementation is the standard and initial management for acute CO poisoning. Normobaric oxygen (NBO) and hyperbaric oxygen (HBO) therapies for CO poisoning have been discussed for several decades. NBO, one-session HBO, two-session HBO, and three-session HBO have not been clearly compared, although there are some syntheses. Therefore, this study aimed to provide an overview of various HBO therapies for CO poisoning. We searched online databases for randomized controlled trials (RCTs) on this topic, and two authors individually extracted data on characteristics, mortality, headache recovery, general fatigue, memory impairment, and difficulty concentrating. Outcomes were pooled using network meta-analysis. We included eight RCTs (n = 1785) that met our eligibility criteria. Pooled estimates showed that HBO had no better outcomes than NBO. Moreover, two-session HBO seemed to have a higher general fatigue rate than NBO, and compared with one-session HBO therapy, it had a higher fatigue rate (risk ratio (RR): 1.29, 95% confidence interval (CI): 1.03-1.62), memory impairment rate (RR = 1.80, 95% CI: 1.01-3.19), and concentration impairment rate (RR = 1.85, 95% CI: 1.19-2.89). HBO may be ineffective for patients with CO poisoning. Therefore, clinicians should consider the available treatment options carefully before recommending HBO to patients.

Correlates of turnover intention among nursing staff in the COVID-19 pandemic: a systematic review

BACKGROUND

During the COVID-19 pandemic, shortage of nursing staff became even more evident. Nurses experienced great strain, putting them at risk to leave their jobs. Individual and organizational factors were known to be associated with nurses' turnover intention before the pandemic. The knowledge of factors associated with turnover intention during the pandemic could help to foster nurses' retention. Therefore, this review aims to identify factors associated with nurses' turnover intention during the COVID-19 pandemic.

METHODS

After a systematic search of six databases, the resulting records were screened in a two-step process based on pre-defined inclusion and exclusion criteria. The included quantitative studies were synthesized qualitatively due to their methodological heterogeneity.

RESULTS

A total of 19 articles were included in the analysis. Individual factors such as health factors or psychological symptoms and demographic characteristics were associated with nurses' turnover intention. Organizational factors associated with turnover intention were e.g., caring for COVID-19 patients, low job control or high job demands, and moral distress. Resilience and supporting leadership could mitigate adverse associations with turnover intention.

CONCLUSIONS

The results help to identify high-risk groups according to individual factors and to develop possible interventions, such as trainings for nurses and their superiors, addressing individual and organizational factors. Future research should focus on longitudinal designs applying carefully defined concepts of turnover intention.

Aerobic, resistance and combined exercise training for patients with amyotrophic lateral sclerosis: a systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to assess the effect of aerobic, resistance and combined exercise training in patients with ALS.

DATA SOURCE

A comprehensive systematic search of CENTRAL, CINAHL, SPORTDiscuss, Embase, Scopus, ProQuest was performed from inception to February 2021.

ELIGIBILITY CRITERIA

The systematic review included all studies that examined the effect of exercise training in ALS patients. Meta-analysis was also carried out on randomized controlled trials (RCTs).

DATA EXTRACTION AND DATA SYNTHESIS

Data related to primary outcomes (functional ability, respiratory function, fatigue, pain, quality of life, upper-body strength, lower-body strength and Vo₂peak) and secondary outcomes (adverse events and feasibility of exercises) was extracted from all studies and systematically reviewed.

RESULTS

16 trials including 532 patients met the inclusion criteria; of these, eight studies were included in this meta-analysis. The meta-analysis found a statistically significant difference in favor of exercise in functional ability (P=0.001), overall quality of life (P=0.03) and Vo₂peak (P=0.01). The included trials were generally of poor quality and had a risk of bias. However, the results of sensitivity analysis, after omitting studies with high risk of bias, showed no statistically significant difference in functional ability (P=0.05), overall quality of life (P=0.12) and Vo2peak (P=0.13). Finally, no significant difference was found in respiratory function, fatigue, pain, and upper-body and lower-body strength.

CONCLUSIONS

The safety and effectiveness of exercise therapy in ALS patients remains unclear and further high quality RCTs with larger sample size are needed. Systematic Review Registration Number PROSPERO CRD42019140011.

Parents' self-reported experiences and information needs related to acute pediatric asthma exacerbations: A mixed studies systematic review

Objective

To systematically review the scientific literature examining parents' experiences and information needs for the management of their child's asthma exacerbations.

Methods

We searched five databases for quantitative and qualitative studies in Canada and the United States from 2002 onwards. A convergent integrated approach and the Mixed Method Appraisal Tool were used to analyze and appraise the evidence, respectively.

Results

We included 84 studies (27 quantitative, 54 qualitative, 3 mixed methods). Some parents lacked confidence in recognizing or managing exacerbations. A few parents were uncertain when and where to seek medical help. The main barrier to accessing care was cost. Impacts on parents included poor sleep, distress, and lifestyle disruptions. Parents felt they lacked information and wanted education on treatments and how to recognize and manage exacerbations via education sessions, written materials, community outreach and online resources.

Conclusion

Improved education for parents may help reduce parents' stress, asthma-related morbidities for children and use of urgent health services.

Innovation

The development of tailored interventions and knowledge translation strategies with input from target audiences (e.g. parents, health care providers) is necessary to meet their information needs and support adherence to clinical recommendations.

•

84 studies reviewed and analyzed using the convergent integrated approach

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Parents lacked confidence in recognizing, treating or seeking care for exacerbations

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Cost was a barrier to care; parents affected by psychosocial impacts

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Parent's desired education on treatments and how to recognize and manage exacerbations

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Interventions and knowledge translation strategies must be developed with parents

Quality versus Risk-of-Bias assessment in clinical research

Assessment of internal validity safeguards implemented by researchers has been used to examine the potential reliability of evidence generated within a study. These safeguards protect against systematic error, and such an assessment has traditionally been called a quality assessment. When the results of a quality assessment are translated through some empirical construct to the potential risk of bias, this has been termed a risk of bias assessment. The latter has gained popularity and is commonly used interchangeably with the term quality assessment. This key concept paper clarifies the differences between these assessments and how they may be used and interpreted when assessing clinical evidence for internal validity.

The effect of occupational exposure to noise on ischaemic heart disease, stroke and hypertension: A systematic review and meta-analysis from the WHO/ILO Joint Estimates of the Work-Related Burden of Disease and Injury

BACKGROUND

The World Health Organization (WHO) and the International Labour Organization (ILO) are developing joint estimates of the work-related burden of disease and injury (WHO/ILO Joint Estimates), with contributions from a large number of individual experts. Evidence from mechanistic data suggests that occupational exposure to noise may cause cardiovascular disease (CVD). In this paper, we present a systematic review and meta-analysis of parameters for estimating the number of deaths and disability-adjusted life years from CVD that are attributable to occupational exposure to noise, for the development of the WHO/ILO Joint Estimates.

OBJECTIVES

We aimed to systematically review and meta-analyse estimates of the effect of any (high) occupational exposure to noise (≥85 dBA), compared with no (low) occupational exposure to noise (<85 dBA), on the prevalence, incidence and mortality of ischaemic heart disease (IHD), stroke, and hypertension.

DATA SOURCES

A protocol was developed and published, applying the Navigation Guide as an organizing systematic review framework where feasible. We searched electronic academic databases for potentially relevant records from published and unpublished studies up to 1 April 2019, including International Trials Register, Ovid MEDLINE, PubMed, Embase, Lilacs, Scopus, Web of Science, and CISDOC. The MEDLINE and Pubmed searches were updated on 31 January 2020. We also searched grey literature databases, Internet search engines and organizational websites; hand-searched reference lists of previous systematic reviews and included study records; and consulted additional experts.

STUDY ELIGIBILITY AND CRITERIA

We included working-age (≥15 years) workers in the formal and informal economy in any WHO and/or ILO Member State but excluded children (<15 years) and unpaid domestic workers. We included randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies with an estimate of the effect of any occupational exposure to noise on CVD prevalence, incidence or mortality, compared with the theoretical minimum risk exposure level (<85 dBA).

STUDY APPRAISAL AND SYNTHESIS METHODS

At least two review authors independently screened titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. We prioritized evidence from cohort studies and combined relative risk estimates using random-effect meta-analysis. To assess the robustness of findings, we conducted sensitivity analyses (leave-one-out meta-analysis and used as alternative fixed effects and inverse-variance heterogeneity estimators). At least two review authors assessed the risk of bias, quality of evidence and strength of evidence, using Navigation Guide tools and approaches adapted to this project.

RESULTS

Seventeen studies (11 cohort studies, six case-control studies) met the inclusion criteria, comprising a total of 534,688 participants (39,947 or 7.47% females) in 11 countries in three WHO regions (the Americas, Europe, and the Western Pacific). The exposure was generally assessed with dosimetry, sound level meter and/or official or company records. The outcome was most commonly assessed using health records. We are very uncertain (low quality of evidence) about the effect of occupational exposure to noise (≥85 dBA), compared with no occupational exposure to noise (<85 dBA), on: having IHD (0 studies); acquiring IHD (relative risk (RR) 1.29, 95% confidence interval (95% CI) 1.15 to 1.43, two studies, 11,758 participants, I² 0%); dying from IHD (RR 1.03, 95% CI 0.93-1.14, four studies, 198,926 participants, I² 26%); having stroke (0 studies); acquiring stroke (RR 1.11, 95% CI 0.82-1.65, two studies, 170,000 participants, I² 0%); dying from stroke (RR 1.02, 95% CI 0.93-1.12, three studies, 195,539 participants, I² 0%); having hypertension (0 studies); acquiring hypertension (RR 1.07, 95% CI 0.90-1.28, three studies, four estimates, 147,820 participants, I² 52%); and dying from hypertension (0 studies). Data for subgroup analyses were missing. Sensitivity analyses supported the main analyses.

CONCLUSIONS

For acquiring IHD, we judged the existing body of evidence from human data to provide "limited evidence of harmfulness"; a positive relationship is observed between exposure and outcome where chance, bias, and confounding cannot be ruled out with reasonable confidence. For all other included outcomes, the bodies of evidence were judged as "inadequate evidence of harmfulness". Producing estimates for the burden of CVD attributable to occupational exposure to noise appears to not be evidence-based at this time.

PROTOCOL IDENTIFIER

10.1016/j.envint.2018.09.040.

PROSPERO REGISTRATION NUMBER

CRD42018092272.

Circulating retinol binding protein 4 levels in coronary artery disease: a systematic review and meta-analysis

BACKGROUND

Retinol binding protein 4 (RBP4) has been proposed to play a role in the pathophysiology of coronary artery disease (CAD), but previous findings on the association of RBP4 levels with CAD are inconsistent.

METHODS

A meta-analysis based on observational studies was conducted to evaluate the association between circulating RBP4 levels and CAD. Databases including PubMed, Web of Science, Embase, Google Scholar and ClinicalTrials.gov database were searched for eligible studies published up to 12 July 2021. Standard mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using the inverse variance heterogeneity (IVhet) and random-effects model for data with moderate and high heterogeneity (I² > 30%) and data with low heterogeneity were analysed using a fixed-effects model (I² ≤ 30%). Moreover, a bias-adjusted quality-effects model was generated, and the prediction interval was also calculated under the random-effects model.

RESULTS

Two nested case-control studies, one cohort study and twelve case-control studies with a total of 7111 participants were included. Circulating RBP4 levels in patients with CAD were comparable to those in the controls under the IVhet model (SMD: 0.25, 95% CI: - 0.29-0.79, I²: 96.00%). The quality-effects model produced consistent results. However, the association turned to be significant under the random-effect model (SMD: 0.46, 95% CI: 0.17-0.75, I²: 96.00%), whereas the 95% predictive interval (PI) included null values (95% PI: - 0.82-1.74). Subgroup analyses illustrated a positive relationship between CAD and RBP4 levels in patients with complications (SMD: 1.34, 95% CI: 0.38-2.29, I²: 96.00%). The meta-regression analysis revealed that the mean BMI of patients (P = 0.03) and complication status (P = 0.01) influenced the variation in SMD.

CONCLUSIONS

There was low-quality evidence that patients with CAD exhibited similar circulating RBP4 levels compared with controls, and high inter-study heterogeneity was also observed. Thus, RBP4 might not be a potential risk factor for CAD. Comparisons among different subtypes of RBP4 with larger sample size are needed in the future.

Bias Assessment in Outcomes Research: The Role of Relative Versus Absolute Approaches

OBJECTIVES

Bias assessment tools vary in content and detail, and the method used for assessment may produce different assessment results in a study if not carefully considered. Therefore, taking an approach to the assessment of studies that produces a similar result regardless of the tool used for assessment (tool independence) is important.

METHODS

A preexisting study that used 25 different quality scales was assessed to examine tool dependence of 2 common approaches to bias assessments-absolute value judgments (defined as the qualitative risk of bias judgment based on a threshold across studies) and relative ranks (defined as the relative probability toward bias of a study relative to the best assessed study). Agreement between each of the 25 scales and a composite scale (that includes all unique safeguards across all scales) was computed (using the intraclass correlation coefficient [ICC]; consistency). Tool dependence was considered present when the ICCs were inconsistent across the 25 scales for the same study.

RESULTS

We found that using relative ranks for tools with different numbers and types of items produced consistent results, with only small differences in the agreement for the various tools with the composite tool, whereas consistency (measured by the ICC) varied considerably when using absolute judgments. Inconsistency is problematic because it means that the assessment result is linked to the scale and not to the study.

CONCLUSIONS

Tool independence is an important attribute of a bias assessment tool. On the basis of this study, the use of relative ranks retains tool independence and therefore produces consistent ranks for the same study across tools.

Effects of exercise training with blood flow restriction on vascular function in adults: a systematic review and meta-analysis

Background

Blood flow restricted exercise (BFRE) improves physical fitness, with theorized positive effects on vascular function. This systematic review and meta-analysis aimed to report (1) the effects of BFRE on vascular function in adults with or without chronic health conditions, and (2) adverse events and adherence reported for BFRE.

Methodology

Five electronic databases were searched by two researchers independently to identify studies reporting vascular outcomes following BFRE in adults with and without chronic conditions. When sufficient data were provided, meta-analysis and exploratory meta-regression were performed.

Results

Twenty-six studies were included in the review (total participants n = 472; n = 41 older adults with chronic conditions). Meta-analysis (k = 9 studies) indicated that compared to exercise without blood flow restriction, resistance training with blood flow restriction resulted in significantly greater effects on endothelial function (SMD 0.76; 95% CI [0.36–1.14]). No significant differences were estimated for changes in vascular structure (SMD −0.24; 95% CI [−1.08 to 0.59]). In exploratory meta-regression analyses, several experimental protocol factors (design, exercise modality, exercised limbs, intervention length and number of sets per exercise) were significantly associated with the effect size for endothelial function outcomes. Adverse events in BFRE studies were rarely reported.

Conclusion

There is limited evidence, predominantly available in healthy young adults, on the effect of BFRE on vascular function. Signals pointing to effect of specific dynamic resistance exercise protocols with blood flow restriction (≥4 weeks with exercises for the upper and lower limbs) on endothelial function warrant further investigation.

Methodological issues of systematic reviews and meta-analyses in the field of sleep medicine: A meta-epidemiological study

An increasing number of systematic reviews and meta-analyses (SRMAs) have been published in the field of sleep medicine. We evaluated the methodological issues of these SRMAs. A protocol was developed in advance. Three databases were searched from inception to October 2019 for SRMAs published in major academic journals of sleep medicine that assessed healthcare interventions. The AMSTAR 2.0 instrument was used to evaluate the methodological issues and a multivariable regression analysis was conducted to investigate potential measures associated with methodological validity. We identified 163 SRMAs. The median number of missing safeguards of these SRMAs was 7 out of 16 (Interquartile range, IQR: 6-9), and on average, two of these missing safeguards were critical weaknesses. Our regression analysis suggested that SRMAs published in recent years (β = 0.16; 95%CI: 0.08, 0.24; p = 0.002), with the first author from Europe (β = 0.08; 95%CI: 0.02, 0.14; p = 0.013) tend to have higher relative methodological ranks. In conclusion, the methodological validity for current SRMAs in sleep medicine was poor. Further efforts to improve the methodological validity are needed.

Ambient Air Pollution, Extreme Temperatures and Birth Outcomes: A Protocol for an Umbrella Review, Systematic Review and Meta-Analysis

Prenatal exposure to ambient air pollution and extreme temperatures are among the major risk factors of adverse birth outcomes and with potential long-term effects during the life course. Although low- and middle-income countries (LMICs) are most vulnerable, there is limited synthesis of evidence in such settings. This document describes a protocol for both an umbrella review (Systematic Review 1) and a focused systematic review and meta-analysis of studies from LMICs (Systematic Review 2). We will search from start date of each database to present, six major academic databases (PubMed, CINAHL, Scopus, MEDLINE/Ovid, EMBASE/Ovid and Web of Science Core Collection), systematic reviews repositories and references of eligible studies. Additional searches in grey literature will also be conducted. Eligibility criteria include studies of pregnant women exposed to ambient air pollutants and/or extreme temperatures during pregnancy with and without adverse birth outcomes. The umbrella review (Systematic Review 1) will include only previous systematic reviews while Systematic Review 2 will include quantitative observational studies in LMICs. Searches will be restricted to English language using comprehensive search terms to consecutively screen the titles, abstracts and full-texts to select eligible studies. Two independent authors will conduct the study screening and selection, risk of bias assessment and data extraction using JBI SUMARI web-based software. Narrative and semi-quantitative syntheses will be employed for the Systematic Review 1. For Systematic Review 2, we will perform meta-analysis with two alternative meta-analytical methods (quality effect and inverse variance heterogeneity) as well as the classic random effect model. If meta-analysis is infeasible, narrative synthesis will be presented. Confidence in cumulative evidence and the strength of the evidence will be assessed. This protocol is registered with PROSPERO (CRD42020200387).

Can Positive Affective Variables Mediate Intervention Effects on Physical Activity? A Systematic Review and Meta-Analysis

Well-developed theories are necessary to guide the public in increasing physical activity (PA) and promoting physical health. The role of positive affective variables (PAVs) in exercise is gaining more attention, but none of the literature has provided a systematic review and quantitative analysis of its mediating role. Therefore, the purposes of this study are (1) to systematically review studies of PA interventions, that use PAVs as the mediating variables, in order to evaluate and provide narrative summaries of these studies; (2) to statistically synthesize evidence for the mechanism of the effects of PAVs on PA outcomes. To conduct an extensive search, a PRISMA-compliant protocol was completed, and five electronic databases had been searched by 1 April 2020. We used a two-stage structural equation modeling (TSSEM) analysis approach to test how interventions trigger the critical PA change process to influence outcomes. The search strategy generated 1,732 papers potentially relevant to this study; forty of these studies met the data extraction criteria for meta-analytic mediation analysis. The path coefficient from intervention to PAV a = 0.26 (95% CI = 0.08 to 0.44), the path coefficient from PAV to PA b = 0.21 (95% CI = 0.13 to 0.28), and the direct effect from intervention to PA is also significant (c = 0.19, 95% CI = 0.12 to 0.26). In addition, the indirect effect of intervention on PA via PAV was statistically significant (c' = 0.05, 95% CI = 0.02 to 0.10). This reveals that PAVs partially mediate the relationship between interventions and PA. Our study is the first to systematically summarize the effects of experimental studies to increase PA through PAVs. It is highly recommended to make future interventions more innovative and to target the PAVs as mediators with higher fidelity.

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.

Family history and pelvic organ prolapse: a systematic review and meta-analysis

INTRODUCTION AND HYPOTHESIS

Numerous analytic observational studies assess family history as a risk factor for POP and report a wide range of associations. This review aims to systematically evaluate the role of family history of POP in relation to POP risk and its recurrence.

METHODS

A review was performed of the PubMed/MEDLINE database with search criteria specifying family history, risk factors, POP, and their synonyms as title/abstract keywords, as well as MESH terms, up to March 2020. We aggregated evidence across studies with fixed effects (FE) and random effects (RE) meta-analysis.

RESULTS

Forty-three articles underwent full-text review. Eighteen independent studies evaluating the relationship between family history of POP and POP risk in 3639 POP cases and 10,912 controls were eligible for meta-analysis. Four studies evaluating family history and POP recurrence in 224 recurrent cases and 400 non-recurrent cases were eligible for inclusion into another meta-analyses. A positive family history of POP is on average associated with 2.3- to 2.7-fold increased risk for POP (RE OR = 2.64; 95% CI = 2.07, 3.35) as well as a 1.4-fold increased risk for POP recurrence (FE OR = 1.44; 95% CI = 1.00, 2.08). Meta-analysis estimates of POP risk varied by study design, definition of family history, and model adjustment status. We found evidence that publication bias and recall bias are a possibility.

CONCLUSIONS

Family history of POP is a risk factor for both POP presence and recurrence. However, reported magnitudes may be overestimates due to confounding, recall bias, and publication bias.

Association between response rates and monetary incentives in sample study: a systematic review and meta-analysis

OBJECTIVE

To investigate the effect of monetary incentive and the dose-response relationship of participants' response rates in surveys.

METHODS

Three databases were searched for randomised controlled trials (RCTs) that investigated the effect of monetary incentives on participants' first and final response rates. First response is defined as the responses after the participant was initially contacted and final response is defined as the responses after several reminders were sent. The potential dose-response relationship of the amount of monetary incentive on the relative response rate (RRR) was established by fitting a restricted cubic spline function based on the robust-error meta-regression model.

RESULTS

105 RCTs were identified. The first RRR increased by 49% (RRR=1.49; 95% CI 1.29 to 1.72) when monetary incentives were provided. Dose-response analysis revealed that an amount between US$6.25 and US$8 had the maximum effect on increasing the first response rate. On average, the final RRR increased almost by 20% (RRR=1.18; 95% CI 1.11 to 1.25) with monetary incentive compared to no-monetary incentive. An amount between US$10 and US$15 had the maximum effect on the final response rate, with an increase in the final RRR of 34% (RRR=1.34; 95% CI 1.19 to 1.51). There was a significant increase in the response rate when two or more reminders were sent.

CONCLUSION

Monetary incentives and reminders improve the response rates. Future studies need to consider providing monetary incentives and sending at least two reminders to increase the response rate and reduce the chances of non-response bias.

Road Traffic Noise Exposure and Depression/Anxiety: An Updated Systematic Review and Meta-Analysis

Unlike other World Health Organization evidence reviews, the systematic review on mental disorders could not provide a quantitative estimate of the effect of environmental noise. With that in mind, we aimed to update it with additional studies published through to 18 August 2019 in order to allow for a formal meta-analysis of the association of residential road traffic noise with anxiety and depression. The quality effects and random effects estimators were used for meta-analysis and the robustness of findings was tested in several sensitivity analyses. Ten studies were included in the qualitative synthesis, from which we extracted 15 estimates for depression (n = 1,201,168) and five for anxiety (n = 372,079). Almost all studies were cross-sectional and the risk of bias in them was generally high. We found 4% (95% CI: -3%, 11%) higher odds of depression and 12% (95% CI: -4%, 30%) of anxiety associated with a 10 dB(A) increase in day-evening-night noise level (Lden). Both models suffered from moderate heterogeneity (55% and 54%), but there was evidence of publication bias only in the depression model. These findings were robust with no evidence of study-level moderators. A sensitivity analysis on an alternative set of categorically-reported estimates supported a linear relationship between Lden and depression. Taking into account an overall quality assessment for the included studies, we conclude that there is evidence of "very low" quality that increasing exposure to road traffic noise may be associated with depression and anxiety.

Comparison of bias adjustment methods in meta-analysis suggests that quality effects modeling may have less limitations than other approaches

BACKGROUND

The quality of primary research is commonly assessed before inclusion in meta-analyses. Findings are discussed in the context of the quality appraisal by categorizing studies according to risk of bias. The impact of appraised risk of bias on study outcomes is typically judged by the reader; however, several methods have been developed to quantify this risk of bias assessment and incorporate it into the pooled results of meta-analysis, a process known as bias adjustment. The advantages, potential limitations, and applicability of these methods are not well defined.

STUDY DESIGN AND SETTING

Comparative evaluation of the applicability of the various methods and their limitations are discussed using two examples from the literature. These methods include weighting, stratification, regression, use of empirically based prior distributions, and elicitation by experts.

RESULTS

Use of the two examples from the literature suggest that all methods provide similar adjustment. Methods differed mainly in applicability and limitations.

CONCLUSION

Bias adjustment is a feasible process in meta-analysis with several strategies currently available. Quality effects modelling was found to be easily implementable with fewer limitations in comparison to other methods.

Road Traffic Noise Exposure and Birth Outcomes: An Updated Systematic Review and Meta-Analysis

Unlike the other WHO evidence reviews, the systematic review on birth outcomes could not provide a quantitative estimate of the effect of environmental noise. With that in mind, we aimed to update it with additional studies published through to 12 May, 2019 to allow for a formal meta-analysis of the association of residential road traffic noise with birth weight, low birth weight (LBW), small for gestational age (SGA), and preterm birth (PTB). The quality effects and random effects estimators were used for meta-analysis and the robustness of findings was tested in several sensitivity analyses. Nine studies were included in the qualitative synthesis, from which we extracted seven estimates for birth weight (n = 718,136 births) and LBW (n = 620,221), and five for SGA (n = 547,256) and PTB (n = 74,609). We found -8.26 g (95% CI: -20.61 g, 4.10 g) (I2 = 87%) lower birth weight associated with a 10 dB(A) increase in day-evening-night noise level (Lden), and this effect became significant in sensitivity analyses. No evidence of significant effects was found for LBW (OR = 1.06; 95% CI: 0.91, 1.23) (I2 = 49%), SGA (OR = 1.02; 95% CI: 0.86, 1.21) (I2 = 90%), or PTB (OR = 1.00; 95% CI: 0.79, 1.27) (I2 = 69%). The quality of evidence for continuous birth weight was graded as "moderate", while for the other outcomes it was deemed "very low". Finally, we discuss limitations of the risk of bias assessment criteria employed by Nieuwenhuijsen et al.