Validity, Reliability, and Responsiveness of the Chronic Heart Failure Questionnaire (Chinese Version)

To the Editor: Despite of the striking rise of the incidence of chronic heart failure (CHF) in the older Chinese population,1 little attention is being paid to the quality of life of these patients, and there is not a valid and reliable Chinese disease-specific quality-of-life measure. The aim of this study was to establish the validity, reliability, and responsiveness of the Chinese version of the Chronic Heart Failure Questionnaire (CHQ-C). CHQ is a disease-specific quality-of-life measure for CHF patients.2 It consists of 20 items and is designed to measure the four domains of impairment caused by CHF, including dyspnea, fatigue, emotional status, and mastery. The response set for all the domains is a seven-point Likert scale, with higher scores indicating better disease-specific quality of life. The high validity, reliability, and responsiveness of CHQ are widely reported.2,3 In this study, the criterion validity of CHQ-C was evaluated by measuring its correlation with the New York Heart Association (NYHA) classification. Construct validity was examined using factor analysis, correlation with the Chinese version of the Hospital Anxiety and Depression Scale (HADS), and known-groups method to compare the use of CHQ-C on people with and without CHF. The internal consistency and 2-week test-retest reliability of CHQ-C were also determined. The responsiveness of CHQ-C was measured using the responsiveness coefficient. A convenience sample of 110 Chinese patients with a documented diagnosis of CHF aged 60 and older with intact cognition (Abbreviated Mental Test score≥6) was recruited upon discharge from the medical unit of a general hospital as the main sample. This sample size was determined by the requirements needed for factor analysis. The mean age±standard deviation of this sample was 77.9±7.8; 48.2% were male. Once eligible subjects were identified and consent to participate in the study was obtained, the research nurse administered the NYHA, CHQ-C, and HADS before discharge. Retesting of the CHQ-C took place 2 weeks later at the subjects' homes. Only 56 subjects with unchanged NYHA scores during the 2-week interval were included for the retesting. Another 64 healthy Chinese elderly people without CHF were also recruited from a community elderly center. The CHQ-C was administered to these healthy subjects for known-groups comparison with the first 64 CHF subjects in the main sample. The demographic and clinical characteristics of the main and community samples were summarized in Table 1. CHQ-C demonstrated significant correlation with the NYHA classification (Spearman r=−0.52, P<.001) and the Chinese version of HADS (Pearson r=−0.74, P<.001). Known-groups comparison revealed significant difference (t=−12.17, P<.001) in the CHQ-C scores between subjects with CHF and healthy subjects. Confirmatory factory analysis supported the original four-factor structure of CHQ. The Cronbach alpha for the overall CHQ-C was 0.95; those for the subscales ranged from 0.82 to 0.94. The intraclass correlation coefficient for the 2-week test-retest reliability was 0.75. The responsiveness coefficient of the overall CHQ-C was 0.63; those for the subscales ranged from 0.6 to 0.7. The CHQ-C is easy to administer and generally requires only 10 to 15 minutes for completion. It is evident that these results support the psychometric properties of CHQ-C in measuring the disease-specific quality of life of Chinese patients with heart failure. It is a valid measure when compared with the NYHA classification and with other constructs associated with quality of life such as the Chinese version of HADS. Known-groups comparison and factor analysis further established the validity of CHQ-C. Confirmatory factor analysis has supported the purported four-factor structure. This instrument also has significant internal consistency, good stability, and responsiveness, but it is important to recognize that, in this study, the psychometric properties of CHQ-C were established from a convenience sample of elderly CHF patients with intact cognitive ability. Limitations therefore exist in generalizing the results of this study to other heart failure populations such as community-dwelling CHF patients, younger CHF patients, or CHF patients with impaired cognitive function. In conclusion, CHQ-C is easy to administer and has significant validity, reliability, and responsiveness. It is recommended as a useful tool in the evaluation of quality of life of older Chinese patients with CHF. A continual examination of its applicability in different CHF populations is recommended to further improve the psychometric qualities of the CHQ-C.