Extent and Reporting of Patient Nonenrollment in Influential Randomized Clinical Trials, 2002 to 2010

JAMA Intern Medicine: April 22, 2013

Because they assign patients to treatment conditions, randomized clinical trials (RCTs) offer unparalleled internal validity for drawing inferences about the efficacy of a medical treatment. Whether such inferences can be generalized is not always clear because many RCTs enroll a low and unrepresentative proportion of all patients.1– 6 The challenges of judging the clinical utility of clinical trial results are increased by poor reporting. The study by Gross et al7 of trials published in leading medical journals from 1999 through 2000 found that only 28% reported the proportion of screened patients who were enrolled. These deficiencies may have been ameliorated in the past decade because the CONSORT statement was revised in 2001 to require more complete information on the enrollment process in reports of clinical trials,8 and because many treatment research fields have been showing greater concern about generating knowledge that better informs clinical practice. Accordingly, the present study assessed the extent to which low enrollment rates are still characteristic of widely cited clinical trials, and whether reporting of enrollment information has improved. Read more