This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Scopus Google Scholar Articles by Pogue, J. Articles by Yusuf, S. PubMed PubMed Citation Articles by Pogue, J. Articles by Yusuf, S. Social Bookmarking                         What's this?

Evaluating the benefit of event adjudication of cardiovascular outcomes in large simple RCTs

Department of Medicine, McMaster University and Population Health Research Institute of McMaster University, Hamilton, ON, Canada, Janice.Pogue{at}phri.ca

Stephen D Walter

Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada

Salim Yusuf

Department of Medicine, McMaster University and Population Health Research Institute of McMaster University, Hamilton, ON, Canada

Background Event adjudication in randomized controlled trials is thought to be a necessary step to remove noise and potential bias from the results [1,2]. However, this hypothesis has not been widely evaluated. We conducted a meta-analysis of a series of cardiovascular outcomes trials and estimated the effect of adjudication on treatment estimates and on the number of outcomes included the trials.

Methods Data were retrieved from all cardiovascular outcomes trials conducted at the Population Health Research Institute (PHRI) between 1993 and 2006. These data included 10 trials with over 9000 events from 95 038 individuals. Differences in the log odds ratios between adjudicated and reported outcomes were analyzed and summarized using a ratio of odds ratios. Both masked and unmasked trials were included in this analysis.

Results There were no effects of event adjudication on the estimates of treatment effect for the primary outcomes, myocardial infarction (MI), stroke, or cardiovascular/vascular death. For the trial primary outcomes, the effect of adjudication vs. reported events was OR ratio = 1.00 [95% confidence interval (CI): 0.97—1.02]. There were also no significant differences in the number of outcomes included in the trials. Results were the same for masked and unmasked trials.

Limitations The number of unmasked trials were small, and this analysis was restricted to cardiovascular endpoints reported from trials managed by a single coordinating center, with similar sets of procedures. Individual patient data were not used for the analysis.

Conclusions This systematic meta-analysis failed to detect any effect of event adjudication on study conclusions and the numbers of events included in the final analyses were minimally changed. Given the considerable effort required to perform adjudication, there is a need to demonstrate that this process does indeed increase the sensitivity of trials. There is a need to conduct more systematic analyses of the effect of event adjudication in other trials to determine if this process is truly worthwhile.

Clinical Trials, Vol. 6, No. 3, 239-251 (2009)
DOI: 10.1177/1740774509105223


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				B. Neal, T. Ninomiya, G. Donnan, N. Anderson, C. Bladin, B. Chambers, G. Gordon, N. Sharpe, J. Chalmers, and M. Woodward Response to Letter by Kerr and Nasco Stroke, November 1, 2009; 40(11): e639 - e640. [Full Text] [PDF]