Active-control equivalence trials and antihypertensive agents

Am J Med. 2001 Nov;111(7):553-8. doi: 10.1016/s0002-9343(01)00900-7.


Purpose: To identify methodological features that affect the validity of conclusions drawn from active-control equivalence trials and to apply these criteria to recently published trials comparing antihypertensive agents from different classes.

Methods: Standard methodological criteria for randomized clinical trials and six additional methodological features that affect the validity of active-control equivalence trials were applied to four recently published large trials that compared different antihypertensive classes and that concluded that their results showed equivalence.

Results: All four of these trials fulfilled standard criteria for randomized trials. However, none fulfilled all of the six additional methodological criteria that affect the validity of active-control equivalence trials, one fulfilled five criteria, two fulfilled two criteria, and one failed to fulfill any of the criteria.

Conclusion: Standard methodological criteria for evaluating superiority trials are inadequate for the interpretation of active-control equivalence trials. The methodological criteria outlined in this article for judging the validity of active-control equivalence trials are not specific to antihypertensive trials and may be applied to trials that test a wide variety of interventions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antihypertensive Agents / pharmacokinetics*
  • Antihypertensive Agents / therapeutic use
  • Evidence-Based Medicine
  • Humans
  • Randomized Controlled Trials as Topic
  • Reproducibility of Results
  • Research Design
  • Therapeutic Equivalency


  • Antihypertensive Agents