Validation of the Spanish version of the Kansas city cardiomyopathy questionnaire.

INTRODUCTION AND OBJECTIVES The Kansas City Cardiomyopathy Questionnaire (KCCQ) is specifically designed to evaluate quality of life in patients with chronic heart failure (CHF). The purpose of this study was to assess the reliability, validity, and responsiveness to change of the Spanish version of the KCCQ. METHODS The multicenter study involved 315 patients with CHF. Patients were evaluated at baseline and at weeks 24 and 26. The KCCQ, the Minnesota Living with Heart Failure Questionnaire (MLHFQ), and the Short Form-36 (SF-36) were administered. Reliability was assessed in stable patients (n=163) by examining test-retest and internal consistency measures between weeks 24 and 26. Validity was evaluated at baseline (n=315) by determining how KCCQ scores varied with New York Heart Association functional class and by comparing scores with those on similar domains of the MLHFQ and SF-36. Responsiveness to change was assessed in patients who experienced significant clinical improvement between baseline and week 24 (n=31) by determining the effect size. RESULTS Reliability coefficients ranged between 0.70 and 0.96 for the different domains. Mean KCCQ scores varied significantly with New York Heart Association functional class (P<.001). Correlations with comparable domains on the other questionnaires were acceptable (e.g. for physical limitation, they were between 0.77 and 0.81). The changes observed at 24 weeks in the majority of KCCQ scores in the subsample that improved corresponded to a moderate effect size (i.e. 0.4-0.6). CONCLUSIONS The Spanish version of the KCCQ has good metric properties (i.e. validity, reliability and responsiveness), which make it suitable for use in evaluating quality of life in Spanish CHF patients.