title: The danger of applying group-level utilities in decision analyses of the treatment of localized prostate cancer in individual patients.
abstract: The optimal management strategy for men who have localized prostate cancer remains controversial. This study examines the extent to which suggested treatment based on the perspective of a group or society agrees with that derived from individual patients' preferences. A previously published decision analysis for localized prostate cancer was used to suggest the treatment that maximized quality-adjusted life expectancy. Two treatment recommendations were obtained for each patient: the first (group-level) was derived using the mean utilities of the cohort; the second (individual-level) used his own set of utilities. Group-level utilities misrepresented 25-48% of individuals' preferences depending on the grade of tumor modeled. The best kappa measure achieved between group and individual preferences was 0.11. The average quality-adjusted life years lost due to misrepresentation of preference was as high as 1.7 quality-adjusted life years. Use of aggregated utilities in a group-level decision analysis can ignore the substantial variability at the individual level. Caution is needed when applying a group-level recommendation to the treatment of localized prostate cancer in an individual patient.
authors.affiliation: Department of Medicine, St. Joseph Mercy Hospital, Ann Arbor, Michigan, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Cowen
authors.forename: B J
authors.initials: BJ
authors.lastname: Miles
authors.forename: D F
authors.initials: DF
authors.lastname: Cahill
authors.forename: R B
authors.initials: RB
authors.lastname: Giesler
authors.forename: J R
authors.initials: JR
authors.lastname: Beck
authors.forename: M W
authors.initials: MW
authors.lastname: Kattan
mesh_terms: D000368:Aged; D003661:Decision Support Techniques; D006801:Humans; D008297:Male; D008875:Middle Aged; D010358:Patient Participation; D018579:Patient Selection; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000523:psychology / Q000601:surgery*; D019057:Quality-Adjusted Life Years