MORE TALK, LESS PAPER - PREDICTING THE ACCURACY OF SUBSTITUTED JUDGMENTS

PURPOSE: TO Study the accuracy of substituted judgments regarding life -sustaining therapies and other therapies made by surrogate decision m akers and to investigate factors associated with more accurate predict ions. PATIENTS AND METHODS: A total of 50 pairs of ambulatory patients and surrogates, chosen according to a legal hierarchy, underwent sepa rate interviews in which surrogates were asked to predict the preferen ces of patients for eight modes of medical therapy in three clinical s cenarios, given only yes or no as response options. Patient preference s, their surrogates' predictions, and the extent of agreement between the two were measured. The total number of correct predictions constit uted the Surrogate Accuracy in Matching Patient Preferences Scale (SAM PPS). Sociodemographic factors associated with agreement were also ass essed. RESULTS: Agreement between patients and surrogates ranged from 57% to 81%. The mean SAMPPS score was 17 of 24 correct. Kappa (k) coef ficients, which measure inter-rater concordance, were positive for 23 of 24 items and were 0.3 or greater (P <0.05) for 14 of 24 items. Rate s of agreement were not related to whether the surrogate interviewed ( surrogate determined by state law) was the person the patient would ha ve chosen as a surrogate or whether the patient had an advance directi ve. In multiple linear regression analysis, both prior discussions of preferences and nonchurchgoing behavior were significantly associated with patient-surrogate agreement, independent of religious denominatio n and race. CONCLUSION: When pressed to choose, surrogates can predict the preferences of patients for life-sustaining therapies with an imp erfect accuracy that nonetheless significantly exceeds the agreement e xpected due to chance alone. Exhorting surrogates to give their ''best estimate'' and encouraging prior discussions may improve accuracy. Ho uses of worship might be important target sites for campaigns to impro ve public awareness about advance directives.