Eliciting health state utilities for Dupuytren's contracture using a discrete choice experiment

Background and purpose An internet-based discrete choice\ud experiment (DCE) was conducted to elicit preferences for a wide\ud range of Dupuytren’s contracture (DC)-related health states. An\ud algorithm was subsequently developed to convert these preferences\ud into health state utilities that can be used to assess DC’s\ud impact on quality of life and the value of its treatments.\ud Methods Health state preferences for varying levels of DC\ud hand severity were elicited via an internet survey from a sample\ud of the UK adult population. Severity levels were deined using a\ud combination of contractures (0, 45, or 90 degrees) in 8 proximal\ud interphalangeal and metacarpophalangeal joints of the index,\ud middle, ring, and little ingers. Right-handed, left-handed, and\ud ambidextrous respondents indicated which hand was preferable\ud in each of the 10 randomly-selected hand-pairings comparing\ud different DC severity levels. For consistency across comparisons,\ud anatomically precise digital hand drawings were used. To anchor\ud preferences onto the traditional 0–1 utility scale used in health\ud economic evaluations, unaffected hands were assigned a utility\ud of 1.0 whereas the utility for a maximally affected hand (i.e., all\ud 8 joints set at 90 degrees of contracture) was derived by asking\ud respondents to indicate what combination of attributes and levels\ud of the EQ-5D-5L proile most accurately relects the impact of\ud living with such hand. Conditional logistic models were used to\ud estimate indirect utilities, then rescaled to the anchor points on\ud the EQ-5D-5L.\ud Results Estimated utilities based on the responses of 1,745\ud qualiied respondents were 0.49, 0.57, and 0.63 for completely\ud affected dominant hands, non-dominant hands, or ambidextrous\ud hands, respectively. Utility for a dominant hand with 90-degree\ud contracture in t h e metacarpophalangeal joints of the ring and\ud little ingers was estimated to be 0.89. Separately, reducing the\ud contracture of metacarpophalangeal joint for a little inger from\ud 50 to 12 degrees would improve utility by 0.02.\ud Interpretation DC is associated with substantial utility decrements.\ud The algorithms presented herein provide a robust and lexible\ud framework to assess utility for varying degrees of DC severity. \ud