Valuing Maintenance of Visual Function in Retinitis Pigmentosa: A Discrete Choice Experiment with Patients and the General Public

BACKGROUND AND OBJECTIVES: Retinitis pigmentosa (RP) is a progressive and sight-threatening condition with few treatment options. Patients with RP experience variable progressive vision deterioration that can severely affect functioning. Currently, there is no published literature to indicate the preferences that patients with RP place on potential treatments. This study compared patient preferences to those of a sample from the general public. METHODS: An online, discrete choice experiment (DCE) elicited preferences of a United States (US) sample for maintaining visual function-related activities of daily living (VF-ADL). The data were stratified by sociodemographic and clinical characteristics. Participants completed best-/worst-choice tasks using predefined attributes and varying levels, including time to deterioration in mobility and ability to read associated with worsening visual function. RESULTS: A total of 150 patients with RP and 301 public participants completed the DCE. By the age of 32-40 years, VF-ADL deteriorated substantially in patients versus public (81% vs 13% reported lower combined mobility/ability to read). Patients with RP placed the greatest value on ability to get around (relative attribute importance [RAI] 51%; standard error [SE] 3.4; 95% confidence interval [CI] 45-58), whereas the public sample preferred ability to get information (RAI 48%; SE 4.7; 95% CI 39-57). Patients with RP placed less weight on extending life expectancy compared with public participants. CONCLUSIONS: Patients with RP demonstrated preferences in VF-ADL and life expectancy associated with deterioration in visual function and potential treatment benefits that differ from those of the public. Considering patient preferences is critical to understand disease burden and estimate the value of therapeutic interventions.