Determination of the clinical importance of study results
- 62 Downloads
Formal statistical methods for analyzing clinical trial data are widely accepted by the medical community. Unfortunately, the interpretation and reporting of trial results from the perspective of clinical importance has not received similar emphasis. This imbalance promotes the historical tendency to consider clinical trial results that are statistically significant as also clinically important, and conversely, those with statistically insignificant results as being clinically unimportant. In this paper, we review the present state of knowledge in the determination of the clinical importance of study results. This work also provides a simple, systematic method for determining the clinical importance of study results. It uses the relationship between the point estimate of the treatment effect (with its associated confidence interval) and the estimate of the smallest treatment effect that would lead to a change in a patient’s management. The possible benefits of this approach include enabling clinicians to more easily interpret the results of clinical trials from a clinical perspective, and promoting a more rational approach to the design of prospective clinical trials.
Key Wordsclinical importance clinical significance study results minimal clinically important difference review
Unable to display preview. Download preview PDF.
- 3.EAFT (European Atrial Fibrillation Study) Group. Secondary prevention in non-rheumatic atrial fibrillation after transient ischemic attack or minor stroke. Lancet. 1993;342:1255–62.Google Scholar
- 11.Feinstein AR. Clinical Biostatistics. Saint Louis: CV Mosby Company; 1977:333.Google Scholar
- 14.Bellamy N, Carrette S, Ford PM, et al. Osteoarthritis antirheumatic drug trials III. Setting the delta for clinical trials—results of a consensus development (Delphi) exercise. J Rheumatol. 1992;20:557–60.Google Scholar
- 29.Cohen J. Statistical Power Analysis for the Behavioral Sciences, 2nd ed. Hillsdale, NJ: Lawrence Erlbaum Associates; 1988:19–27.Google Scholar
- 32.Anonymous. Significance of significance. N Engl J Med. 1968;278:1232–3.Google Scholar
- 34.Sackett DL, Haynes RB, Guyatt GH, Tugwell P. Clinical Epidemiology. A Basic Science for Clinical Medicine, 2nd ed. Boston: Little, Brown and Company; 1991.Google Scholar
- 45.Dalby DM, Sellors JW, Fraser FD, Fraser C, van Ineveld C, Howard M. Effect of preventive home visits by a nurse on the outcomes of frail elderly people in the community: a randomized controlled trial. CMAJ. 2000;62:497–500.Google Scholar