Abstract 319: Development of a Knowledge Measure to Evaluate a Decision Aid for Patients Choosing Between Home and Hospital Based Cardiac Rehabilitation
Background: Home-based cardiac rehabilitation (CR) has similar efficacy as center-based CR, but the choice of which meets the needs of individual patients is preference-sensitive. Our objective was to develop a knowledge measure to be used to evaluate a shared decision-making tool for patients choosing between home and center-based CR.
Methods: We generated 11 true/false questions about home and hospital-based CR. The statements were reviewed for accuracy by 8 exercise physiologists. Cognitive testing was performed with 10 patients using the “think-aloud” method to understand their interpretation of what each item was asking. The statements were then revised to improve acceptability and clarity. We tested the knowledge statements in a sample of 124 participates from the lay public recruited via mTurk. Psychometric properties of item difficulty, item uncertainty, and index of discrimination were evaluated. Differences between groups based on education level, age, sex, and race/ethnicity were also evaluated.
Results: Of 124 respondents 66% were female, 69% were white, 69% were between 18-44 years of age, and 89% had at least some college education. On average respondents answered 70% of questions correctly. Item difficulty ranged from 51% to 98% correct. Item uncertainty ranged from 9% to 36%. Index of discrimination was highest for questions 2 (75%), 7 (74%) and 9 (68%). (see Table) Within each subgroup, the following groups had the highest average score: African Americans, (77%), females (74%), advanced degree (80%) and ages 55-64 (78%).
Conclusion: The knowledge measure developed in this study can be used to assesses knowledge about key concepts central to making an informed decision about home vs. hospital-based CR. This knowledge measure will be further validated and used to evaluate a decision aid for patients in our safety net hospital system choosing between home and hospital-based CR.
