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Cherry-picking by trialists and meta-analysts can drive conclusions about intervention efficacy
Evan Mayo-Wilson1, Tianjing Li1, Nicole Fusco1
1Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205.
Journal of Clinical Epidemiology
|August 27, 2017
Summary
Discrepancies in data from multiple sources significantly impact systematic reviews of randomized clinical trials (RCTs). These data disagreements can alter the interpretation of trial results and meta-analyses for drugs like gabapentin and quetiapine.
Area of Science:
- Clinical Trials and Evidence Synthesis
- Pharmaceutical Research and Drug Efficacy
- Biostatistics and Meta-Analysis
Background:
- Systematic reviews of randomized clinical trials (RCTs) are crucial for evidence-based medicine.
- Discrepancies in data reporting across various sources can potentially bias review outcomes.
- Understanding the impact of data source disagreements is vital for accurate interpretation of trial results.
Purpose of the Study:
- To investigate whether disagreements among multiple data sources influence systematic reviews of randomized clinical trials (RCTs).
- To assess the effect of data source discrepancies on the interpretation of trial outcomes and meta-analyses.
Main Methods:
- Identified eligible RCTs for gabapentin (neuropathic pain) and quetiapine (bipolar depression).
- Compared data from public sources (journal articles) with nonpublic sources (clinical study reports [CSRs] and individual participant data [IPD]).
- Analyzed variations in trial design, risk of bias, and results reporting across different data sources.
Main Results:
- Most RCTs were reported in journal articles, but CSRs provided more comprehensive trial design and risk of bias information.
- CSRs and IPD contained the most detailed results, with significant variations found for meta-analyzable outcomes.
- Selective reporting of results within single trials could change conclusions from effective to ineffective for gabapentin and from medium to small effect for quetiapine.
Conclusions:
- Disagreements across data sources demonstrably affect effect size, statistical significance, and overall interpretation in trial data and meta-analyses.
- The choice of reported results from a single trial can lead to conflicting conclusions.
- Ensuring comprehensive data access and transparent reporting is essential for reliable systematic reviews.
Keywords:
Clinical trialsMeta-analysisReporting biasRisk of bias assessmentSelective outcome reportingSystematic reviewsMore Related Videos
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