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randomized clinical trial; randomized controlled trial (RCT)

An experimental study that uses random assignment to create treatment & control groups so that changes can be inferred or attributed to the experimental treatment. Advantages: - strong design for determining causation [1] Disadvantages: - expensive, time consuming, limited follow-up duration - not practical for many clinical situations [1] - study intervention might unduly influence data outcome - study population may not represent population of interest Notes: - randomization may be by individuals, randomized controlled trial, or by cluster (i.e. nursing unit), cluster-randomized trial - caution should be used when generalizing the results of a randomized controlled trial to populations other than those who would meet inclusion but not exclusion criteria for the study - surrogate outcomes (i.e. biomarker such as LDL cholesterol or interim outcome such as progression-free survival) are more likely to show results favoring treatment than patient- relevant outcomes [3] * see level of evidence for reliability of scientific investigations

Related

intention-to-treat analysys

Specific

cluster randomized trial unnamed randomized controlled trial

General

clinical trial

References

  1. Medical Knowledge Self Assessment Program (MKSAP) 16, 17. American College of Physicians, Philadelphia 2012, 2015
  2. Ho PM, Peterson PN, Masoudi FA. Evaluating the evidence: is there a rigid hierarchy? Circulation. 2008 Oct 14;118(16):1675-84. PMID: 18852378
  3. Ciani O et al. Comparison of treatment effect sizes associated with surrogate and final patient relevant outcomes in randomised controlled trials: Meta-epidemiological study. BMJ 2013 Jan 29; 346:f457 PMID: 23360719