AN INTERNATIONAL COMPARISON OF PHYSICIANS JUDGMENTS OF OUTCOME RATES OF CARDIAC PROCEDURES AND ATTITUDES TOWARD RISK, UNCERTAINTY, JUSTIFIABILITY, AND REGRET

Objective. Compare U.K. and U.S. physicians' judgments of population p robabilities of important outcomes of invasive cardiac procedures; and values held by them about risk, uncertainty, regret, and justifiabili ty relevant to utilization of cardiac treatments. Design. Cross-sectio nal study. Setting. University hospital and VA medical center in the U nited States; two teaching hospitals in the United Kingdom. Participan ts. 171 housestaff and attendings at U.S. teaching hospitals; 51 physi cian trainees and consultants at U.K. hospitals. Measures. Judgments o f probabilities of severe complications and deaths due to Swan-Ganz ca theterization, cardiac catheterization, percutaneous transluminal coro nary angioplasty (PTCA), and coronary artery bypass grafting (CABG); j udgments of malpractice risks for case vignettes; Nightingale's risk-a version instrument; Gerrity's reaction-to-uncertainty instrument; ques tions about need to justify decisions; responses to case vignettes reg arding regret. Results. The U.S. physicians judged rates of two bad ou tcomes of cardiac procedures (complications due to cardiac catheteriza tion; death due to CABG) to be significantly higher (p less than or eq ual to 0.01) than did the U.K. physicians (U.S. medians, 5 and 3.5, re spectively; U.K. medians 3 and 2). The median ratio of (risk of malpra ctice Suit I error of omission)/(risk of suit I error of commission) j udged by U.K. physicians, 3, was significantly (p = 0.0006) higher tha n that judged by U.S. physicians, 1.5. The U.K. physicians were less o ften risk-seeking in the context of possible losses than the U.S. phys icians (odds ratio for practicing in the U.K. as a predictor of risk s eeking 0.3, p = 0.003). The U.K. physicians had significantly more dis comfort with uncertainty than did the U.S. physicians, as reflected by higher scores on the stress scale (U.K. median 48, U.S. 42, p = 0.000 1) and the reluctance-to-disclose-uncertainty scale (U.K. 40, U.S. 37, p < 0.0001) of the Gerrity instrument. There was no clear internation al difference in perceived need to justify decisions, or in regret. Co nclusions. The results were not clearly consistent with the uncertaint y hypothesis that international practice variation is due to differenc es in judged rates of outcomes of therapy or with the imperfect-agency hypothesis that practice variation is due to differences in physician s' personal values. The causes and implications of practice variations remain unclear.