Journal of Clinical Epidemiology

BackgroundLittle guidance is available on how composite outcomes should be interpreted, especially in situations of varied direction in the association across the event subtypes. I proposed an index to evaluate the bias attributable to composite outcomes (BACO) and applied it in recently published clinical trials. MethodsI defined the BACO index as the ratio between logarithms of the association measures of both a composite outcome and its most relevant component (e.g., any-cause mortality). By...

IntroductionSystematic literature reviews (SLRs) are critical for informing clinical research and practice, but they are time-consuming and resource-intensive, particularly during Title and Abstract (TiAb) screening. Loon Lens, an autonomous, agentic AI platform, streamlines TiAb screening without the need for human reviewers to conduct any screening. MethodsThis study validates Loon Lens against human reviewer decisions across eight SLRs conducted by Canadas Drug Agency, covering a range of dr...

Evidence syntheses adhering to systematic literature searching techniques are a cornerstone of evidence-based health care. Beyond term-based searching in electronic databases, citation searching is a prevalent search technique to identify relevant sources of evidence. However, for decades, citation searching methodology and terminology has not been standardized. We performed an evidence-guided four-round Delphi consensus study with 27 international methodological experts in order to develop the ...

BackgroundPublished studies in the life and health sciences often employ sample sizes that are too small to detect realistic effect sizes. This shortcoming increases the rate of false positives and false negatives, giving rise to a potentially misleading scientific record. To address this shortcoming, many researchers now use point-and-click software to run sample size calculations. ObjectiveWe aimed to (1) estimate how many published articles report using the G*Power sample size calculation so...

ObjectiveSystematic reviews (SRs) are essential to ensure that decisions are informed by an up-to-date and complete understanding of the relevant research evidence. Conducting SRs within a doctoral thesis can reduce redundant, harmful and unethical research, identify knowledge gaps, and help the doctoral student obtain important skills to conduct and use research. The output and learning process of SRs overlaps with the aims of doctoral programs. We aim to explore to what extent SRs are included...

BackgroundCochrane is a recognized source of quality evidence that informs health-related decisions. As an organization, it represents a global network of diverse stakeholders. Cochranes key organizational values include diversity and inclusion, to enable wide participation and promote access. However, the diversity of Cochrane review authorship has not been well summarized. ObjectiveThe aim of this study was to examine the distribution of country, region, language, and gender diversity in the ...

ObjectiveTo determine the reproducibility of biomedical systematic review search strategies. DesignCross-sectional meta-research study. PopulationRandom sample of 100 systematic reviews indexed in MEDLINE in November 2021. Main Outcome MeasuresThe primary outcome measure is the percentage of systematic reviews for which all database searches can be reproduced. This was operationalized as fulfilling six key PRISMA-S reporting guideline items (database name, multi-database searching, full searc...

BackgroundThe COVID-19 pandemic has resulted in a mass of academic papers being published in a very brief span of time. Our aim was to compare the amount and reporting characteristics of COVID-19 related peer-reviewed and pre-prints publications. We also investigated the amount of ongoing trials and systematic reviews. Methods and findingsA cross-sectional study of publications covering the COVID-19 pandemic time frame, up to May 20, 2020 was conducted. PubMed with appropriate combinations of M...

ObjectivesWe investigated meta-research studies that evaluated adherence to prominent reporting guidelines (CONSORT, PRISMA, STARD, STROBE) in health research studies to determine the proportion that (1) provided an explanation for how complex guideline items were rated for adherence and (2) provided results from individual studies reviewed in addition to aggregate results. We also examined the conclusions of each meta-research study to assess redundancy of findings across studies. DesignCross-...

BackgroundThe number of problematic randomized clinical trials (RCTs) has risen sharply in recent decades, posing serious challenges to the integrity of the healthcare evidence ecosystem. ObjectiveTo investigate whether retraction of problematic RCTs could reduce evidence contamination. DesignRetrospective cohort study SettingA secondary analysis of the VITALITY Study database. Participants1,330 retracted RCTs with 847 systematic reviews. MeasurementsThe difference in the median number (and...

In this study, we examined the discrepancy between large studies and small studies in meta-analyses of rare event outcomes and the impact of Peto versus the classic odds ratios (ORs) through empirical data from the Cochrane Database of Systematic Reviews that collected from January 2003 to May 2018. Meta-analyses of binary outcomes with rare events (event rate [≤]5%), with at least 5 studies, and with at least one large study (N[≥]1000) were extracted. The Peto and classic ORs were used as...

ObjectivesTo test authors experience of applying the STrengthening the Reporting of Observational Studies in Epidemiology-nutritional epidemiology (STROBE-nut) on a recently published paper. Correct understanding of the items on the reporting guidelines could lead to appropriate use. Designa cross sectional study, with a convenient sample. SettingParticipants were asked to return the STROBE-nut data collection template filled on recently published papers. Next, an interview was organised to co...

The synthesis of treatment effects relies on systematic reviews of intervention trials. This process is often laborious due to the need for precise search queries and manual study identification. Recent advancements in database architecture and natural language processing (NLP) offer a potential solution by enabling faster, more flexible searches and automated extraction of information from unstructured texts. Our study assesses the effectiveness of NLP-based literature searches within a novel ...

IntroductionObservational studies are fraught with several biases including reverse causation and residual confounding, which may limit the credibility of reported associations. Overview of reviews of observational studies (i.e., umbrella reviews) synthesize systematic reviews with or without meta-analyses of cross-sectional, case-control, and cohort studies, and may also aid in the grading of the credibility of reported associations. The number of published umbrella reviews has been increasing ...

STRUCTURED ABSTRACTO_ST_ABSObjectiveC_ST_ABSTo better understand the characteristics of, and requirements for, lay summaries by reviewing journals, global health organisations, professional medical associations and multi-disciplinary organisations, consumer advocacy groups and funding bodies. DesignUsing a scoping review methodology, we searched the websites of each identified data source to determine if they require, suggest, or refer to lay summaries. Two reviewers extracted lay summary writi...

BackgroundInterrupted time series (ITS) studies contribute importantly to systematic reviews of population-level interventions. However, there is no search filter designed to identify only ITS studies from bibliographic databases. We aimed to develop and validate search filters to retrieve ITS studies in MEDLINE and PubMed. MethodsA set of 1,017 known ITS studies (published 2013-2017) were analysed using text mining to generate candidate terms. A population set of 1,398 time-series studies were...

BackgroundFrom 2006 to 2019, Cochrane reviews could be designated "stable" if they were not being updated but highly likely to be current. This provides an opportunity to observe practice in ending systematic reviewing and what is regarded as enough evidence. MethodsWe identified Cochrane reviews designated stable in 2013 and 2019 and reasons for this designation. For those with conclusions stated to be so firm that new evidence is unlikely to change them, we assessed conclusions, strength of e...

ObjectivesTo examine changes in completeness of reporting and frequency of sharing data, analytic code and other review materials in systematic reviews (SRs) over time; and factors associated with these changes. DesignCross-sectional meta-research study. SampleA random sample of 300 SRs with meta-analysis of aggregate data on the effects of a health, social, behavioural or educational intervention, which were indexed in PubMed, Science Citation Index, Social Sciences Citation Index, Scopus and...

BackgroundJournals may respond to integrity concerns by publishing an editorial response (editorial notice, expression of concern (EoC) or retraction). We investigated whether the type of editorial response affected citation rates. MethodsWe obtained citations for 172 randomised controlled trials (RCTs) with integrity concerns (41 had editorial notices, 38 EoCs and 23 retractions) and control RCTs from the same journal and year. Monthly citation rates up to 60 months before and after editorial ...

ObjectiveTo investigate the prevalence of bias attributable to composite outcome (BACO) in clinical trials. Study design and settingWe searched PubMed for randomized clinical trials where the primary outcome was a binary composite that included all-cause mortality among its components from January 1, 2019, to December 31, 2020. For each trial, the BACO index was calculated to assess the correspondence between effects on the composite outcome and that on mortality. This systematic review was reg...