Development and Validation of a Patient-Reported Outcome Measure for patients with Inherited Cardiac Conditions: Integrating Genetic Well-Being

Introduction: Literature on the quality of life (QoL) in patients with inherited cardiac conditions (ICC) is limited, and existing studies mostly rely on generic health-related QoL measures. The latter may not capture important aspects of ICC such as heritability. This study aims to develop a disease-specific patient-reported outcome measure (PROM) for ICC patients, with a particular focus on integrating heritability-related aspects into traditional QoL domains. Methods: We conducted a qualitative study involving focus groups with ICC patients. These sessions aimed to capture the QoL concerns of ICC patients. The transcripts were thematically analysed using ATLAS.ti. The initial item pool was mapped onto traditional QoL models. We adapted these models to address hereditary concerns (Figure 1). The preliminary item list was refined through feedback from expert healthcare professionals and additional patient focus groups, ensuring the relevance and comprehensiveness of the items. The next phase will involve psychometric validation of the developed PROM, including assessments of construct validity, internal consistency, and factor structure. Results: The focus groups involved 23 patients (56% female) from 4 university hospitals, with hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, long QT syndrome, catecholaminergic polymorphic ventricular tachycardia or Brugada syndrome. Analysis of transcripts generated 491 unique codes. After applying exclusion criteria and removing duplicates, 51 codes were retained, resulting in the preliminary 91-item list. The items were categorized into 4 QoL domains: Being (37%), Belonging (15%), Becoming (18%), and the novel domain Genetic well-being (30%). Feedback from expert interviews and follow-up patient focus groups led to the refinement of the item list, resulting in a final instrument of 100 items. These items are assessed using a 5-point Likert scale (Figure 2), with 20 items including open-ended questions to capture additional patient insights. Psychometric validation is scheduled in several European countries and Australia. Conclusion: We developed a novel PROM for patients with an ICC, incorporating the novel domain of Genetic well-being to address heritability alongside more generic health-related QoL domains. The instrument is now ready for psychometric validation, to refine and establish its utility for research and clinical practice.