Development and Validation of the AFImpact: 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 α 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.