How important are willingness to participate studies in encouraging patient enrollment in oncology trials?

Abstract

Despite the 3.5% increase in the FY2014 National Institutes of Health budget compared with the previous cycle [1], the recent budget sequestration and increasing funding uncertainty for clinical trials underscores the importance of optimizing the design of cancer clinical trials to ensure successful completion, including a priori evaluation of strategies to maximize patient accrual. Currently, only half of National Cancer Institute (NCI) Cooperative Group trials are completed. Several factors contribute to the limited success rate of these trials, including poor study designs, insufficient funding, and regulatory hurdles. Despite a first-rate US health care system that has the greatest number of available oncology clinical trials, it is disappointing that only 3–5% of adults enroll in clinical trials [2]. The potential for both selective enrollment and underenrollment is increasingly cited by scientific review committees in questioning the feasibility of proposed trials, which is not surprising since cancer clinical trials are becoming increasingly complex, often combining multiple treatment modalities, employing targeted therapies, and having more radiology and biologic correlative studies. Nearly a decade ago, Halpern proposed prospective preference assessment (PPA) as a method to improve patient enrollment and identify subgroups of patients who may benefit from a potential trial [3]. With PPA, potential subjects are interviewed using five key components: presentation of a hypothetical trial resembling the planned trial, assessment of the patient’s understanding of the study design, open-ended questioning to assess motivations for and concerned about the planned trial, written questionnaires to evaluate patient’s stated willingness to participate in the planned trial, and assessment of their willingness to participate when one or more identified important factors is varied [3]. We recently used PPA to conduct the first series of studies of patients’ willingness to participate in radiation oncology trials. In 2011, our group performed a PPA of patients’ willingness to participate in a randomized control trial of proton beam therapy versus intensity-modulated radiotherapy for localized prostate cancer. We undertook this study because of the high cost of the two proposed treatment arms, as well as the potential for strong patient preferences for one treatment versus the other, both of which contributed to our uncertainty regarding the feasibility of the proposed trial. In our study, we prospectively enrolled and interviewed 46 patients using purposeful sampling to ensure a diverse sample based on travel distance, age, race and physician provider. Using semi-structured interviews, we presented patients with a hypothetical trial description and asked several open-ended and focused follow-up questions regarding both their motivations for and concerns about trial enrollment. Using qualitative research analytic techniques, we identified over 20 factors that impacted patients’ willingness to participate in the proposed randomized How important are willingness to participate studies in encouraging patient enrollment in oncology trials?