Purpose: To use a discrete choice experiment (DCE) to learn about how vulnerable adults in North Carolina value different aspects of colorectal cancer (CRC) screening programs.
Methods: We used prior research, focus groups, and expert opinion to develop a DCE that examined four key attributes of potential CRC screening programs: 1) choice of screening tests offered (fecal occult blood testing (FOBT) alone, colonoscopy (COL) alone, choice of FOBT and COL, choice of FOBT, COL or radiological screening); 2) travel distance required to obtain screening (0, 15, 30, or 45 miles); 3) co-payment or reward for having screening ($1000 co-payment, $100 co-payment, $25 co-payment, $0 copayment, $10 reward, or $100 reward); 4) proportion of follow-up costs paid out of pocket (0%, 5%, 50%, 100%). We then used Sawtooth software to generate a 16-task DCE. After pilot testing to ensure comprehension, we enrolled a sample of English-speaking average-risk adults ages 50-74. Participants were recruited from rural NC communities with low rates of CRC screening, had either no insurance or only public insurance, and had low or fixed incomes. They received basic information about CRC screening and potential program features, then completed the DCE and survey questions. We analyzed DCE responses using Hierarchical Bayesian methods to produce group and individual-level part-worth utilities for the 4 attributes, and also calculated individual-level importance scores. Each individual’s highest importance score was considered the “DCE-calculated most important attribute.”
Results: We enrolled 150 adults. Mean age was 55.9 (range 50-74), 55% were women, 76% White and 19% African-American; 87% had annual household income under $30,000; and 51% were uninsured. From the survey, proportion of out of pocket follow-up costs was most frequently reported to be most important (42% of participants); testing options was next most frequent (32%). From the DCE, follow-up cost was most frequently found to be the DCE-calculated most important attribute (49%), followed by screening test reward/co-payment (43%). Agreement between the survey and DCE-calculated most important attribute was modest (45%). On both the survey and DCE, participants valued having test choice and the opportunity to choose FOBT.
Conclusions: Screening test rewards /co-payments and follow-up costs are important program characteristics, particularly for vulnerable populations. Programs to encourage screening should take these factors into account to be most effective.
