Enrolling in deep brain stimulation research for depression: influences on potential subjects' decision making

Ethical concerns regarding early-phase clinical trials of DBS for treatment-resistant depression (TRD) include the possibility that participants' decisions to enroll might be motivated by unrealistic expectations of personal benefit or minimization of risks.

Thematic analyses were conducted on a sample of 26 adults considering participation in two DBS trials. Influences on the decision making of these potential DBS trial participants were derived from responses to questions posed in the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), a semi-structured interview designed to evaluate decisional capacity to consent to research.

Participants cited numerous factors as influential in their enrollment decisions, including perceived lack of other treatment options, desire to take initiative, beliefs about DBS as a novel treatment, possibility of DBS efficacy, hoped-for improvements, potential risks and disadvantages of DBS or clinical trial participation, and altruism. No individual expressed a set of motivations or influencing factors that suggested compromised decision-making capacity or diminished voluntariness of decision making.

These results suggest that individuals make the decision to enroll in early-phase trials of DBS for TRD based on a number of complex and sometimes idiosyncratic considerations, and that the trials that were studied utilized sufficiently robust informed consent processes. These findings offer evidence that the emerging research area of DBS can be advanced in an ethically sound manner, provided that safeguards and processes for discussing trials with participants are carefully and proactively enacted.