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No inexplicable disagreements between real-world data-based nonrandomized controlled studies and randomized
Tim Mathes1, Tanja Rombey1, Oliver Kuss2
1Institute for Research in Operative Medicine, Faculty of Health, School of Medicine, Witten/Herdecke University, 51067 Cologne, Germany.
Journal of Clinical Epidemiology
|December 28, 2020
Summary
Nonrandomized controlled studies based on real-world data (NRCS-RWDs) largely agree with randomized controlled trials (RCTs). Disagreements were often due to risk of bias in NRCS-RWDs, not external validity issues.
Area of Science:
- Epidemiology
- Biostatistics
- Health Services Research
Background:
- Real-world data (RWD) is increasingly used in comparative effectiveness research.
- Nonrandomized controlled studies using RWD (NRCS-RWDs) are an alternative to randomized controlled trials (RCTs).
- Assessing the agreement between NRCS-RWDs and RCTs is crucial for evidence synthesis.
Purpose of the Study:
- To assess disagreements between NRCS-RWDs and RCTs.
- To identify potential causes of discrepancies in treatment effect estimates.
- To evaluate the impact of internal and external validity on agreement.
Main Methods:
- Systematic literature search for studies comparing NRCS-RWDs and RCTs on the same clinical question.
- Meta-epidemiological analysis to quantify agreement between study types.
- Assessment of internal and external validity threats.
- Identification of probable causes for observed disagreements.
Main Results:
- Included 12 studies with 15 treatment effect estimates comparing NRCS-RWDs and RCTs.
- Confidence intervals overlapped for 12 of 15 estimates, indicating general agreement.
- Only two substantial differences were observed, attributed to risk of bias in NRCS-RWDs.
- No more disagreements than expected by chance were found.
Conclusions:
- Well-conducted NRCS-RWDs can yield results comparable to RCTs for certain clinical questions.
- Risk of bias in NRCS-RWDs is a primary driver of disagreement.
- Threats to external validity had minimal impact on treatment effect estimate disagreements.
Keywords:
External validityInternal validityMeta-epidemiologyNonrandomized studiesRandomized controlled trialsReal-world evidenceMore Related Videos
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