Assessment of the Decision-Making Capacity for Clinical Research Participation in Patients With Advanced Cancer in the Last Weeks of Life

Context: Few studies have examined how clinicians assess decision-making capacity for research in the last weeks of life. Objectives: We examined the decision-making capacity for participation in a research study and its association with clinician impression and delirium among patients with cancer with days to weeks of life expectancy. Methods: Patients admitted to our palliative and supportive care unit were approached for a prospective observational study. We assessed for their decision-making capacity based on clinical impression of physician and nurse, Memorial Delirium Assessment Scale (MDAS), and the MacArthur Competency Assessment Tool for Clinical Research (MacCAT-CR). Results: Among the 206 patients, 131 patients (64%) did not require MacCAT-CR assessment because they were overtly delirious or unresponsive; 37 (18%) patients were alert but did not complete the MacCAT-CR assessment for other reasons, and 38 patients (18%) completed the MacCAT-CR assessment. Among these 38 patients, five (13%) patients were incapable and had normal albeit significantly higher MDAS scores compared with those who were capable (1.8 vs. 4.2; P = 0.002). Compared against MacCAT-CR and MDAS, the overall agreement with capacity assessment with a clinician was 88% (95% CI 82–93) for physicians and 90% (95% CI 82–94) for nurses. The area under the receiver operating characteristics curve was 0.93 (95% CI 0.88–0.96) for physicians and 0.94 (95% CI 0.89–0.97) for nurses, suggesting high discrimination. Conclusion: Most patients in the palliative and supportive care unit lacked decision-making capacity for participation in clinical research. Clinician impression had high accuracy. Few patients with normal MDAS were found to be incapable with MacCAT-CR assessment.