Background: Past research has documented that primary care physicians and family members are often inaccurate when making substituted judgments for patients without advance directives (ADs). This study compared the accuracy of substituted judgments made by primary care physicians, hospital-based physicians, and family surrogates on behalf of elderly outpatients and examined the effectiveness of ADs in improving the accuracy of these judgments.
Participants and methods: Participants were 24 primary care physicians of 82 elderly outpatients, 17 emergency and critical care physicians who had no prior experience with the patients, and a baseline comparison group of family surrogates. The primary outcome was accuracy of physicians' predictions of patients' preferences for 4 life-sustaining treatments in 9 hypothetical illness scenarios. Physicians made substituted judgments after being provided with no patient AD, patient's value-based AD, or patient's scenario-based AD.
Results: Family surrogates' judgments were more accurate than physicians'. Hospital-based physicians making predictions without ADs had the lowest accuracy. Primary care physicians' accuracy was not improved by either AD. Accuracy and confidence in predictions of hospital-based physicians was significantly improved for some scenarios using a scenario-based AD.
Conclusions: Although ADs do not improve the accuracy of substituted judgments for primary care physicians or family surrogates, they increase the accuracy of hospital-based physicians. Primary care physicians are withdrawing from hospital-based care in growing numbers, and emergency medicine and critical care specialists most often are involved in decisions about whether to begin life-sustaining treatments. If ADs can help these physicians better understand patients' preferences, patient autonomy more likely will be preserved when patients become incapacitated.