Factors Affecting Study Subject Recruitment and Retention in a Major Depressive Disorder Study




Karnkowska, Barbara


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The purpose of a clinical trial is to demonstrate safety, tolerability and efficacy of investigational medications before receiving FDA approval for medical use. The success of clinical trials heavily relies on quick patient recruitment as well as long-term patient retention throughout the duration of the study. Recruitment and retention have been identified as the most expensive components of research, in some instances consisting of up to 33% of the designated budget spanning from phase I to III trials [3]. In light of the rising costs of pharmaceutical research, it is important to investigate factors implicated in patient recruitment and retention throughout a clinical trial. Focusing on a Major Depressive Disorder study, an analysis of the following factors determining patient involvement in clinical trials was proposed: sex, age, weight, distance from site, marital status, concomitant medications, comorbid diseases, and work status, among others. Using logistical regression model, a retrospective study was conducted in order to characterize a profile of an optimized patient. Logistic regression analysis of data revealed that the most significant determinant of patient enrollment into a Major Depressive Disorder study is the use of an antidepressant treatment (ADT) at the time of pre-screening consultation. A closer look revealed that a potential patient was three times more likely to enroll in the study if he or she was on an ADT than an individual without the treatment. Further analysis confirmed model significance and result validity, as well as prompted ideas for further research.