The cardiac health profile: content, reliability and validity of a new disease-specific quality of life questionnaire.

BACKGROUND

The Cardiac Health Profile (CHP) is a new questionnaire for assessing health-related quality of life of patients with cardiovascular diseases. It consists of three parts assessed as follows: the degree of angina pectoris (the CCS scale), the quality of life and subjective scoring of psychosocial 'cost-benefit'. Parts II and III of the questionnaire are based on visual analogous scales and consist of 16 and two questions, respectively, covering nine areas. This quality of life questionnaire has been tested for reliability, validity and sensitivity.

METHODS

Eighty consecutive patients with angina pectoris, who were waiting for coronary angiography, were enrolled in the study. Four sets of data were deleted since the respondents were not able to fill in the forms correctly. Fifty-one healthy volunteers constituted a control group.

RESULTS

Reliability was assessed by a 'test and retest' method. The resulting correlation coefficient was 0.927 (P = 0.0009). Internal consistency was studied by applying Cronbach's alpha. The internal alpha-coefficient was 0.89. Concurrent validity was studied by comparing the outcome in the Nottingham Profile with the CHP. The intercorrelation indicated good concurrent validity (r = 0.753, P = 0.0001). The construct validity was assessed by performing a factor analysis. The sensitivity was assessed in three ways: analysis of kurtosis, comparison of the group of angina pectoris patients with a healthy control group and by comparing CHP results before a standard intervention (coronary artery bypass grafting) and after. The CHP showed in all of these ways a good sensitivity with statistically significant differences between angina patients and the control group (P < 0.0001). A significant improvement in health-related quality of life was also found after coronary artery bypass grafting compared with before (P = 0.02).

CONCLUSIONS

The CHP has been found to be reliable, valid and sensitive and the present findings encourage use of the questionnaire in clinical trials for its further development.