Development and Validation of the AF Impact: An Atrial Fibrillation-Specific Measure of Patient-Reported Health-Related Quality of Life

Background: Improvement in health-related quality of life is a key therapeutic goal of disease management in atrial fibrillation (AF). OBJECTIVES: To describe the development of the AFImpact, an AF-specific health-related quality-of-life patient-reported outcome measure. METHODS: Development and validation of the AFImpact comprised a qualitative stage, consisting of a literature review and concept elicitation interviews (91 patients with AF), item generation, and cognitive debriefing (30 patients with AF), and a quantitative stage, consisting of evaluation of the instrument's psychometric properties (313 patients with AF). Preliminary responsiveness to change was assessed in 118 patients undergoing cardioversion. RESULTS: On the basis of the literature review and concept elicitation interviews, 75 items were generated. Factor analyses guided a reduction to 18 items. Three domains were confirmed: vitality (7 items), emotional distress (8 items), and sleep (3 items). The 18-item AFImpact demonstrated high item convergent and discriminant validity. Cronbach a coefficients showed high internal consistency reliability. Test-retest reliability of individual items in stable patients (n = 33) was satisfactory, with intraclass correlation coefficients ranging from 0.61 to 0.86. All three AFImpact domain scores differentiated patients who reported different levels of overall health, thereby supporting known-groups validity. Scores for each item improved after cardioversion, with effect sizes ranging from -0.19 to -0.65. CONCLUSIONS: Psychometric evaluations support the reliability and validity of the AFImpact as a patient-reported outcome instrument to measure the impact of AF, with preliminary results in patients undergoing cardioversion supporting responsiveness to change. Copyright (C) 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.