A Randomized Study of Scleroderma Health State Values
A Picture Is Worth a Thousand Words, and Quite a Few Utilities
Published In: Medical Decision Making, v. 29, no. 1, Jan./Feb. 2009, p. 7-14
Posted on RAND.org on December 31, 2008
OBJECTIVE: Assigning utilities to hypothetical health states requires that the health states be described in adequate detail, but there is no agreement on exactly how health states should be described. The authors assess utilities from the general public for health states common in scleroderma (SSc) by describing the health states in writing alone v. with photographs of patients with SSc. METHODS: Subjects rated several SSc health states on a 0 to 100 rating scale (RS) and completed computer-assisted time tradeoff (TTO; range, 0.0-1.0) and standard gamble (SG; range, 0.0-1.0) assessments. Half of the subjects were assigned to be shown photographs of patients with SSc health states in addition to written health state descriptions, whereas the other half were given only the written descriptions. RESULTS: Of the 213 participants, 133 (62%) were female, 138 (65%) were Caucasian, and 62 (29%) were African American. Median RS, TTO, and SG scores for 5 SSc health states ranged from 20 to 70, 0.28 to 0.94, and 0.50 to 0.90, respectively. In bivariate analyses, showing pictures was associated with lower RS scores for 2 of 5 health states and lower SG values for all 5 health states (P < 0:05 for comparison of pictures v. no pictures), but with no difference in TTO values. Multivariable analyses revealed negative associations between pictures and SG valuations for the 3 most severe SSc health states (R2 range, 0.04-0.08). CONCLUSION: Adding pictures of people with SSc to written health state descriptions can affect valuations of SSc health states, although the effect differs by valuation measurement method and by health state severity.