Further Explorations of Medical Decisions for Individuals and for Groups

Abstract

Background. Important discrepancies between clinical practice and health policy may be related to the ways in which physicians and others make decisions about individuals and groups. Previous research has found that physicians and laypersons asked to consider an individual patient generally make different decisions than those asked to consider a group of comparable patients, but this discrepancy has not been observed in more recent studies. This study was designed to explore possible reasons for these findings. Methods. Prospective jurors (N = 1,013) each made a recommendation regarding a risky treatment for an incurable blood condition. Perspective (individual vs group) was crossed with uncertainty frame (probability vs frequency) and response wording (original vs revised) in a 2 x 2 x 2 between-participants design. Results. When the strength of participants' recommendations was considered, the effects of perspective, uncertainty frame, and response wording were not statistically significant. When recommendations were dichotomized, participants in the revised-response-wording conditions were more likely to recommend treatment to the group than to the individual. Conclusions. These results conflict with previous findings for this scenario and suggest that reported differences between decisions for individuals and decisions for groups are not robust. Key words: decision making; expected utility theory; practice guidelines; risk; survey research. (Med Decis Making 2000;20:39-44)

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