Evaluating the evidence for evidence‐based medicine: are randomized clinical trials less flawed than other forms of peer‐reviewed medical research?

Evidence‐based medicine considers randomized clinical trials (RCTs) to be the strongest form of evidence for clinical decision making. To test the hypothesis that RCTs have fewer methodological flaws than non‐RCTs, limitations of 17,591 RCTs and 39,029 non‐RCTs were characterized. Panels of experts assembled to write meta‐analyses evaluated this literature to determine which articles should be included in 316 meta‐analytic reviews. Overall, 38.7% of RCTs evaluated were excluded from review for an identified flaw. Commonly identified flaws in RCTs were as follows: insufficient data provided to evaluate the study (9.6% of 17,591 RCTs); inadequate randomization (9.0%); inadequate blinding (4.9%); and duplicative publication (4.4%). Overall, 20.2% of all published medical research has an identified methodological flaw, with RCTs having as many limitations as non‐RCTs.—Steen, R. G., Dager, S. R., Evaluating the evidence for evidence‐based medicine: are randomized clinical trials less flawed than other forms of peer‐reviewed medical research? FASEB J. 27, 3430–3436 (2013). www.fasebj.org