Objectives: To develop a tool for multidimensional measurement of the quality of life, which was psychometrically sound, short, and easy to administer for patients with hypertension.
Methods: A sample of 1115 hypertensive patients aged 20 or above in Cheong-Song County was studied from June 1997 to October 1998. In the development of the instrumental stage, the authors first conceptualized the quality of life. Item generation, item reduction, and questionnaire formatting were followed. Item-level (item descriptive, missing%, item internal consistency, item discriminant validity) analysis, scale-level (scale descriptive, floor and ceiling effect) analysis, and other tests(Cronbach's alpha, inter-dimension correlations, factor analysis, clinical validity) were performed to evaluate the validity and reliability of the new measurement scale. After 1 year, responsiveness and confirmatory factor analysis were performed.
Results: The results of both item-level and scale-level analyses were acceptable. An acceptable degree of internal consistency was observed for each of the dimensions (Cronbach's alpha was 0.60 or higher). Inter-dimension correlations were below 0.50 and the factor analysis result was the same as the intended dimension structure. Correlation coefficients between perceived health status, stress and dimensions were proven to be acceptable. The result of comparing dimensional score means among ADL and MMSE-K groups above 60 years was statisticalIly significant (p < 0.05). The result of confirmatory factor analysis concluded that the dimensional structure model was well fitted. However, the result of responsiveness test using sensitivity and specificity was unsatisfactory.
Conclusions: The newly developed measurement scale is psychometrically reliable and valid instrument for measuring quality of life in hypertensive patients.