DOES PROCESS UTILITY EXIST - A CASE-STUDY OF WILLINGNESS-TO-PAY FOR LAPAROSCOPIC CHOLECYSTECTOMY

This paper is concerned with the concept of process utility in health care. The paper begins by outlining the reasons why it might be import ant to include process utility in health care evaluation. Problems in defining process and outcome are then outlined, after which the discus sion turns to how process utility might be detected empirically. Willi ngness to pay (WTP) is suggested as one means of doing so. The methods and results of a survey to test for the existence of process utility using WTP applied to laparoscopic cholecystectomy are reported. Cholec ystectomy patients on a hospital waiting list were asked about their W TP for laparoscopic rather than conventional cholecystectomy. Willingn ess to pay was used in two ways to examine whether process is in the u tility function. First, respondents were randomly allocated to receive different descriptions of laparoscopic and conventional cholecystecto my; one group receiving a description of differences between the treat ments in terms of outcomes only, whilst the other group received infor mation on differences in the process of treatment as well as on differ ences in outcomes. The groups were then compared in terms of their WTP . Second, regression analysis was used to test for the association bet ween WTP and respondents' ratings of reasons for their WTP, some of th ese reasons reflecting process aspects and others reflecting outcome a spects. The results lead to rejection of the hypothesis that informati on on process of care would lead to higher WTP. However, due to the de sign of the study and the difficulties in defining process and outcome , it cannot be concluded that process utility does not exist. The pape r concludes by suggesting alternative methods of testing for the exist ence of process utility. Copyright (C) 1997 Elsevier Science Ltd