Reliability of a German version of the Kansas City Cardiomyopathy Questionnaire (KCCQ) administered via telephone

To date, there is no validated telephone version of the Kansas City Cardiomyopathy Questionnaire (KCCQ) available to collect data about health-related quality of life among patients with heart failure (HF). We assessed the reliability of the German KCCQ administered via telephone in comparison to the self-administered version. Patients with HF admitted to the outpatient clinic of the University Hospital Würzburg were consecutively identified and recruited. Patients completed (a) the self-administered version of the KCCQ, and (b) the telephone-based interview performed by trained raters. The sequence of both approaches was randomized. For the between-method agreement, the intraclass correlation coefficient (ICC) was calculated using a non-parametric, rank-based approach. We analysed data from sixty-one HF patients. The median KCCQ overall summary score was 84.8 (interquartile range (IQR) 71.6-76.9). The test-retest reliability between the self-administered and the telephone interview showed good agreement for the total symptom score, the clinical score and the overall summary core: ICC 0.75, 95 % confidence interval (CI) 0.72-0.79; ICC 0.80, CI 0.77-0.84; ICC 0.83, CI 0.80-0.86, respectively. The German KCCQ administered via telephone showed good test-retest reliability, indicating its applicability to collect data about health status among HF patients over the phone.