Evaluation of the Treatment Tradeoff Method in Rectal Cancer Patients: Is Surgery Preference Related to Outcome Utilities?

Background. The treatment tradeoff method (TTM) has been developed specifically for decision making at the level of the individual patient. The task is tailored to the clinical decision problem at hand and may therefore be more relevant to patients than methods of outcome valuation. Despite its wide use in oncology research, few methodological studies regarding validity have been conducted. Objective and Methods. The present study evaluates the validity of the TTM in rectal cancer patients who had undergone either 1 of 2 surgery types: 1 requiring a permanent stoma (stoma group) and 1 involving a postoperative risk of fecal incontinence (no-stoma group). The authors relate the surgery preference scores to the utilities of the 2 main surgery outcome states as well as to their utility difference. Results. Surgery preference was more strongly associated with the utility difference (r > 0.54 in the total patient group) than with the utilities of the surgery outcome states per se (r < 0.44 in the total patient group). In the stoma group, surgery preference was especially related to the utility of incontinence and in the no-stoma group especially to the utility of a permanent stoma. Conclusions. Patients indeed use their valuations of treatment outcomes states, especially those they are less familiar with, in determining their preference for one treatment over another. In clinical practice, the TTM may be used to obtain an indication of the treatment preference of an individual patient and may also be helpful to detect patients' motives to choose one treatment over another.