Our results challenge current policy and law advocating instructional advance directives as a means of honoring specific patient wishes at the end of life. Future research should explore other methods of improving surrogate decision making and consider the value of other outcomes in evaluating the effectiveness of advance care planning.

To honor the wishes of an incapacitated patient, surrogate decision makers must predict the treatment decisions patients would make for themselves if able. Social psychological research, however, suggests that surrogates' own treatment preferences may influence their predictions of others' preferences. In 2 studies (1 involving 60 college student surrogates and a parent, the other involving 361 elderly outpatients and their chosen surrogate decision maker), surrogates predicted whether a close other would want life-sustaining treatment in hypothetical end-of-life scenarios and stated their own treatment preferences in the same scenarios. Surrogate predictions more closely resembled surrogates' own treatment wishes than they did the wishes of the individual they were trying to predict. Although the majority of prediction errors reflected inaccurate use of surrogates' own treatment preferences, projection was also found to result in accurate prediction more often than counterprojective predictions. The rationality and accuracy of projection in surrogate decision making is discussed.

Objective: To compare health benefits achieved in a transtheoretical model‐chronic disease (TM‐CD) minimal intervention for obesity vs. augmented usual care (AUC). Research Method and Procedures: This was a 2‐year, randomized clinical trial with overweight or obese men and women from 15 primary care sites. AUC (n = 336) included dietary and exercise advice, prescriptions, and three 24‐hour dietary recalls every 6 months. TM‐CD care (n = 329) included AUC elements plus “stage of change” (SOC) assessments for five target behaviors every other month, mailed SOC and target behavior—matched workbooks, and monthly telephone calls from a weight‐loss advisor. Weight change was the primary outcome. Results: Repeated measures models under the missing at random assumption yielded nonsignificant adjusted differences between the AUC and TM‐CD groups for weight change, waist circumference, energy intake or expenditure, blood pressure, and blood lipids. The pattern of change over time suggested that TM‐CD participants were trying harder to impact target behaviors during the first 6 to 12 months of the trial but relapsed afterward. Sixty percent of trial participants maintained their baseline weights for 18 to 24 months. Discussion: A combination of mailed patient materials and monthly telephone calls based on the transtheoretical model and some elements of chronic disease care is not powerful enough, relative to AUC, to alter target behaviors among overweight primary care patients in an obesogenic environment. AUC may be sufficient to maintain weights among at‐risk primary care patients.

Very few individuals may desire the standard approach to advance care planning whereby preferences for specific life-sustaining treatments are documented and these requests are strictly followed near death. Instead, patient autonomy may be better served by emphasizing discussion of process preferences and leeway in decision making.

Preferences for life-sustaining treatment are dependent on the context in which they are made, and thus individuals may express different treatment preferences when they are healthy than when they are ill. These results challenge a key psychological assumption underlying the use of instructional advance directives in end-of-life decision making.