Substituted Judgment: How Accurate Are Proxy Predictions?

Abstract

Substituted judgment has been proposed as a method of promoting the autonomy of the mentally incapacitated patient, but little is known about the accuracy of surrogate decision makers in reflecting the true wishes of patients. In this study, surrogate decision makers' views (those of primary care providers and close family members) were compared with the decisions of currently competent chronically ill elderly patients, using a hypothetic cardiopulmonary resuscitation scenario under circumstances of current health and progressive dementia. Concordance between patients and their surrogates was evaluated by assessing percent agreement, kappa coefficient (for concordance beyond chance), and directionality of discrepant responses. Most patient respondents chose to be resuscitated in both scenarios. Although patients predicted that both their physicians (90%) and family members (87%) would accurately represent their wishes, neither family members nor physicians, in fact, were able to adequately predict patients' wishes in both scenarios (kappa less than or equal to 0.3 in all scenarios; percent agreement range, 59% to 88%). Few patients had ever discussed their resuscitation preferences with either their family member (16%) or their physician (7%). These results cast doubt on the usefulness of a strict substituted judgment standard as an approach to medical decision making for patients with diminished mental capacity.

Do Older Adults Know Their Spouses' End-of-Life Treatment Preferences?

“…5 Where items are structured to permit such responses, expressed preferences do vary continuously (Libbus and Russell 1995; PrincipeRodriguez et al 1999;Seckler et al 1991;Suhl et al 1994;Sulmasy et al 1998). …”

“…5 Where items are structured to permit such responses, expressed preferences do vary continuously (Libbus and Russell 1995;PrincipeRodriguez et al 1999;Seckler et al 1991;Suhl et al 1994;Sulmasy et al 1998). where η 1 = surrogate preferences (latent); η 2 = spouse preferences (latent); Y PG = surrogate response for self, pain condition; Y CIG = surrogate response for self, cognitive impairment condition; Y P'S = surrogate report on spouse preference, pain condition; Y CI'S = surrogate report on spouse preference, cognitive impairment condition; Y PS = spouse response for self, pain condition; Y CIS = spouse response for self, cognitive impairment condition; the λ ij are coefficients to be estimated, and the ε i are random errors. In addition to the λ ij , the parameters of the model are the variances and covariances of the latent preferences (Ψ j ) and the variances and covariances of the errors in variables .…”

Substituted Judgment: The Limitations of Autonomy in Surrogate Decision Making

“…A second line of research examines the concordance between a patient and his or her doctors, [14][15][16][17][18][19][20][21][22][23][24] or chosen surrogates. 17,18,21,[25][26][27][28][29][30][31][32] In such studies, individuals are asked what they would want for themselves in particular circumstances.…”

Legal Aspects of End-of-Life Care

“…In a review 18 of 16 studies, surrogates incorrectly predicted patients' endof-life treatment goals in one-third of cases. In another study, 19 even though patients thought both their family members (87%) and their physicians (90%) could accurately represent the patients' wishes, accuracy with the wishes ranged from 59% to 88%. Of note, few patients in the study 19 had ever discussed their resuscitation preferences with either a family member (16%) or a physician (7%).…”

“…In another study, 19 even though patients thought both their family members (87%) and their physicians (90%) could accurately represent the patients' wishes, accuracy with the wishes ranged from 59% to 88%. Of note, few patients in the study 19 had ever discussed their resuscitation preferences with either a family member (16%) or a physician (7%). These findings emphasize the need for patients and surrogates to discuss preferences before the patients lose decision-making capacity.…”