Interpreting Clinical Trial Outcomes for Optimal Patient Care: A Survey of Clinicians and Trainees

Abstract

ABSTRACT Background Evaluation of the clinical importance of outcomes in research studies is an essential element of clinical decision making. Objective To understand how clinicians and trainees weigh the importance of different types of clinical outcomes in drug trials. Methods A self-administered paper survey contained 4 scenarios asking participants to rate (1, “no proof” to 10, “good proof”) the extent to which 4 study outcomes provided “proof that the new drug might help people.” Outcomes included (1) a surrogate outcome; (2) a surrogate-enriched composite outcome; (3) stroke mortality; and (4) all-cause mortality. The primary study metrics were mean ratings for each of the 4 outcome types, and the proportion ranking outcome importance of all-cause mortality > stroke mortality > surrogate-enriched composite or surrogate alone. Results A convenience sample of 549 clinicians and trainees at 2 medical centers completed the survey (response rate: 87% medical students, 80% internal medicine residents, 69% general medicine faculty, and 41% physician experts). The surrogate-enriched composite outcome and stroke mortality were rated the most important evidence for benefit (6.6 and 6.4, respectively), with all-cause mortality and a surrogate outcome being rated significantly lower (5.2 and 4.6, respectively). In addition, 48% of clinicians rated improvement in all-cause mortality as more valuable than an improvement in a surrogate marker. Only 21% rated all-cause mortality as more valuable than a surrogate-enriched composite outcome. Conclusions These findings raise concerns that clinicians and trainees may not interpret trial evidence in a way that promotes the best care for patients.