Ten simple rules for reading randomized controlled trials
DOI:
https://doi.org/10.21142/mecp.2026.1.2.e022Keywords:
Randomized Controlled Trials as Topic, GRADE Approach, Evidence-based medicine, Bias, Decision MakingAbstract
Randomized controlled trials (RCTs) are central to evidence-based medicine, yet their interpretation can be challenging for clinicians without formal training in research methods. This article presents ten practical rules to guide the reading, interpretation, and application of RCTs, focusing on common pitfalls and key concepts. These include clarifying the study question using the PICO framework, distinguishing primary from secondary outcomes, understanding the purpose and limits of randomization, interpreting effect sizes and confidence intervals, and considering absolute as well as relative measures. The rules also emphasize systematic assessment of risk of bias, evaluation of external validity, and careful consideration of study limitations and their direction of bias. Finally, readers are encouraged to contextualize findings within the broader body of evidence before applying them to practice. Aimed at students and clinicians beginning to appraise biomedical evidence, these rules are intended as an accessible starting point to support more informed and critical interpretation of RCTs.
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