Patients' preferences regarding the process and outcomes of life-saving technology. An application of conjoint analysis to liver transplantation.

The economic technique of conjoint analysis was used to assess the relative importance of health outcome versus several process attributes (e.g., waiting time, continuity of contact with the same medical staff) in determining patients' preferences for liver transplantation services. The attributes were established by reference to the literature and through initial qualitative interviews with liver transplant recipients (n = 12). Following a pilot study of 40 patients, a sample of patients (n = 213) who have received a liver transplant at the Queen Elizabeth Hospital in Birmingham were surveyed. The technique of conjoint analysis was used to ascertain the relative importance of the attributes included in the exercise and to estimate the marginal rates of substitution (MRS) between different attributes. A useable response rate of 89% was achieved. Although a small proportion of respondents (15%) exhibited dominant preferences for the chance of success attribute, the majority of respondents indicated that they would be prepared to exchange a reduction in health outcome for an improvement in the process characteristics of the liver transplantation service. The results of this study have potentially important implications for the assessment of the benefits of medical technologies since they suggest that, even in the extreme case of life-saving interventions, the preferences of respondents may not be dependent solely upon health outcomes but may also be determined by attributes associated with the process of care.