Psychometric properties of the KCCQ-12 in an european cohort of patients with heart failure

Background Despite medical advances, patients with heart failure continue to suffer from poor quality of life due to worsening symptoms and functional limitations. Therefore, it is important to understand the multidimensional facets of quality of life in these patients. The Kansas City Cardiomyopathy Questionnaire is a commonly used quality of life assessment tool worldwide. However, However, there is still a lack of knowledge about its psychometric properties. Purpose The aim of this study was to investigate the psychometric properties of the KCCQ-12 and its measurement invariance in a cohort of European patients with heart failure. Methods Participants (n=510, median age=72, IQR=18, 58% males) completed the KCCQ-12 alongside measures of clinical psychosocial severity. A confirmatory factor analysis was used to establish factorial validity; internal consistency was determined using the Omega coefficient and the model-based internal consistency coefficient. Zero-order correlations between the KCCQ-12 scores and clinical and psychosocial measures were performed to test convergent validity. Multigroup confirmatory factor analysis was conducted to test measurement invariance across patients with preserved vs reduced ejection fraction. Results Confirmatory factor analysis confirmed a four-factor solution, with the domains of physical limitations, symptom frequency, quality of life, and social interference. Internal consistency was excellent (Omega coefficients ranging from 0.83 and 0.90, and internal consistency index of 0.94). The KCCQ-12 scores significantly correlated with ejection fraction, New York Heart Association class, quality of life, anxiety, depression, symptom burden, and the KCCQ-23 Overall Summary score, which adequately supported the convergent validity of the KCCQ-12. Measurement invariance was confirmed at the partial scalar and strict level. Conclusions These findings support the validity and reliability of the KCCQ-12, both in patients with reduced and preserved ejection fraction. Hence, this version can be confidently used both in research and clinical practice to measure quality of life of heart failure patients.