A Structural Analysis of Health-Related Quality of Life Dimensions

Abstract

Of critical importance in the applications of quality of life theory and measurement to clinical situations is the need to know how the different components of quality of life relate to each other and what these relationships mean. To answer this question, the present study reanalyzes data collected 6 months after surgery on 469 patients with cardiovascular problems. The data were factor analyzed and five factors were extracted, namely, Symptoms of Illness, Neurological Dysfunction, Interpersonal Relationships, Morale, and Socioeconomic Status. Because the factor scores derived from these five factors intercorrelated, we were able to hypothesize causal models suggesting how the factors might affect each other. Two competing models were tested against the data using LISREL. A crucial difference between the two models was that in one, Symptoms lowered Morale whereas in the other, low Morale aggravated Symptoms, i.e., a psychosomatic effect. The first model fitted the data very well in contrast to the second model which did not fit the data at all. The authors consider the implications of the first model for improving quality of life in cardiac patients.