Methods
This study was part of a larger project assessing the utility of a web-based self-care intervention for AF patients, within the context of the COVD-19 pandemic. Patients were recruited from the patient panel of electrophysiologists at the University of North Carolina through electronic outreach. Patients who consented and were enrolled in the intervention study completed several electronic surveys prior to and following the intervention, including surveys of demographic information, health information, and knowledge/attitudes/beliefs about COVID-19, as well as other validated surveys.
For the purposes of this study, patient responses on the CALM, PROMIS-29, and AFEQT were analyzed. The PROMIS-29 is a widely validated and used assessment of general quality of life including eight domains: pain intensity and interference, fatigue, sleep disturbance, physical functioning, depression, anxiety, and ability to participate in social roles and activities.15 The AFEQT is a well-established and widely used, four-factored descriptive measure of disease-specific patient quality of life, with demonstrated validity and reliability (internal consistency >.88 on all factors).12 This measure is used to describe the patient experience of AF, specifically symptoms, daily activities, and perceptions of treatment (i.e. concerns and satisfaction). Medical record review was conducted to obtain information about health and relevant comorbidities. This study was approved by the Institutional Review Board at the University of North Carolina at Chapel Hill (IRB #20-1121).
Items for the CALM measure were patterned after items from the Self-care of Heart Failure Index (SCHFI) (REF: Riegel) and modified by a cardiac electrophysiologist (AG) and clinical health psychologist (SFS) to tailor them to AF. Next, multiple AF providers including medicine, psychology, and nursing provided feedback on relevance and comprehensiveness of the items to reflect the patient experience with confidence and AF. The preliminary items were then employed in the current study.
Statistical Analyses . The current study utilized survey responses, prior to intervention, in order to establish the validity of a stand-alone measure of confidence in self-management of AF, the CALM, and to describe and compare scores on this measure with other survey data (e.g. AFEQT).
Principle Components Analysis (PCA) was used to analyze the 16-item CALM measure, in order to group variables into key components. A varimax rotation was employed to simplify each component, minimizing the amount of variance within each component and maximizing the variance between components. Cronbach’s alpha was then used to assess reliability of the total measure, as well as the reliability of the individual components.
Correlational analyses and independent samples t-tests were then used to assess the relationships and differences in scores on several demographic, health, and QOL variables.