BACKGROUND: Correspondence between patient preferences and patient-reported outcomes (PROs) is of interest among researchers. Research indicates low optimism and numeracy may be associated with difficulty or lack of participation in making treatment-related decisions.
OBJECTIVES: We investigated whether low optimism and low self-reported numeracy were associated with evidence of difficulty making decisions in a discrete-choice experiment (DCE).
METHODS: Preferences for a treatment to delay type 1 diabetes were elicited using a DCE among 1,501 parents in the United States. Respondents chose between two hypothetical treatments or an opt-out (no treatment) in a series of choice questions. The survey included the Life Orientation Test– Revised (a measure of optimism) and the 3-item Subjective Numeracy Scale. We used random-parameters logit (RPL) models to test for differences in preferences across subgroups defined by PRO scores and 5-class latent class analyses where membership probability was predicted by PRO scores.
RESULTS: In RPL subgroup models, respondents with below median optimism had different and disordered preferences compared with high optimism (P = 0.000), but preferences of respondents with above median numeracy were not different compared with lower numeracy (P = 0.0714). Latent class analyses found those with lower optimism scores had a higher probability of membership in a class that chose opt-out and had disordered preferences (P value for optimism coefficient: P = 0.032). Those with lower self-reported numeracy were more likely to be in a class with a strong preference for the opt-out (P = 0.000) or a class with a preference for the opt-out and avoiding serious treatment-related risks (P = 0.015).
CONCLUSIONS: Two PROs helped identify differences in preferences in a DCE. If respondents with lower optimism and lower numeracy are more likely to choose an opt-out or have disordered preferences in a DCE, it may indicate that they have difficulty completing choice tasks.
