Expected utility theory (EUT) has been challenged as a descriptive theory in many contexts. The medical decision analysis context is not an exception. Several researchers have suggested that rank dependent utility theory (RDUT) may accurately describe how people evaluate alternative medical treatments. Recent research in this domain has addressed a relevant feature of RDU models-probability weighting-but to date no direct test of this theory has been made. This paper provides a test of the main axiomatic difference between EUT and RDUT when health profiles are used as outcomes of risky treatments. Overall, EU best described the data. However, evidence on the editing and cancellation operation hypothesized in Prospect Theory and Cumulative Prospect Theory was apparent in our study. we found that RDU outperformed EU in the presentation of the risky treatment pairs in which the common outcome was not obvious. The influence of framing effects on the performance of RDU and their importance as a topic for future research is discussed.