Doctors' and patients' preferences for participation and treatment in curative prostate cancer radiotherapy.
OBJECTIVE
Physicians hold opinions about unvoiced patient preferences, so-called substitute preferences. We studied whether doctors can predict preferences of patients supported with a decision aid.


METHODS
A total of 150 patients with prostate cancer facing radiotherapy were included. After the initial consultation, without discussing any treatment choice, physicians gave substitute judgments for patients' decision-making and radiation dose preferences. Physicians knew that several weeks later, patients would be empowered by a decision aid supporting a choice between two radiation doses involving a trade-off between disease-free survival and adverse effects. Subsequently, patient preferences for decision making (whether or not they wanted to choose a radiation dose) and for treatment (low or high dose) were obtained. The chosen radiation dose actually was administered.


RESULTS
Of the patients studied, 79% chose a treatment; physicians believed that 66% of the patients wanted to choose. Agreement was poor (64%; = 0.13; P = .11), and was better as patients became more hopeful (odds ratio [OR] = 4.4 per unit; P = .001) and as physicians' experience increased (OR = 1.09 per year; P = .02). Twenty percent of physicians' preferences, 51% of physicians' substitute preferences, and 71% of patients' preferences favored the lower dose; agreement was again poor (70%; = 0.2; P = .03).


CONCLUSIONS
Physicians had problems predicting the preferences of patients empowered with a decision aid. They slightly underestimated patients' decision-making preferences, and underestimated patients' preferences for the less toxic treatment. Counseling might be improved by first informing patients-possibly using a decision aid--before discussing patient preferences.
Stalmeier
Peep F M
PF
Department of Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. p.stalmeier@mta.umcn.nl
van Tol-Geerdink
Julia J
JJ
van Lin
Emile N J Th
EN
Schimmel
Erik
E
Huizenga
Henk
H
van Daal
Willem A J
WA
Leer
Jan-Willem
JW
D000368:Aged; D015331:Cohort Studies; D003657:Decision Making; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016017:Odds Ratio; D017060:Patient Satisfaction / Q000706:statistics & numerical data*; D010819:Physician's Role; D010817:Physician-Patient Relations; D011336:Probability; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods / Q000706:statistics & numerical data; D020266:Radiotherapy, Conformal / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome
D017430:Prostate-Specific Antigen