Reasons for Non-Participation of Turkish Patients in International Clinical Trials

Objective: Turkey is an emerging country in terms of clinical research with a large population of patients not previously exposed to clinical trials. Despite its increasing importance in the clinical research field, the recruitment process is very difficult for various reasons and may become a serious research limitation. A project was designed and implemented with a view to understanding the perceptions of Turkish participants to clinical trials.Methods: Investigators were given a questionnaire booklet to complete with information about all patients that were potentially eligible for active involvement in international clinical trials. A total of 39 investigators from eight cities participated in the survey and they provided information on 410 patients who were candidates for ongoing international trials.Results: A total of 306 out of 410 patients were eligible for the trials; the remaining 104 patients were ineligible based on inclusion and exclusion criteria, and physician estimation on patient’s compliance. Of the 306 eligible patients, 80 refused to sign an informed consent form. The two most common reasons for refusing to participate in a clinical trial were the influence of patients’ relatives (36.7%) and the risk of adverse events (27.8%). These were followed by the need for additional visits/tests (18.9%), the risk of being treated with inactive agents - i.e. placebo- (15.2%), and the probability of being randomized to unknown products (12.7%).Conclusion: Patient barriers for enrollment include the ‘guinea pig’ perception held by patients and/or relatives, anxiety caused by uncertainty, additional demands of the trial, and concerns about information and consent. (Marmara Medical Journal 2012;25:78-82)