Methodological triangulation showed the poorest quality of life in the youngest people following treatment of coronary artery disease: a Longitudinal study

The purpose of the longitudinal study was to describe, explain and understand the subjective health related quality of life (HRQoL) and life course of people (N=280) with coronary artery disease (CAD) during the period following the onset of the disease, the process of therapy and the period of rehabilitation. Methodological triangulation was used in this research. The significance of the results obtained with quantitative and qualitative methods was evaluated by means of meta-analysis. A longitudinal quantitative study was undertaken through the year after the treatments (medication, balloon angioplasty or bypass surgery), and 19 persons attended thematic interviews 1 year after the treatments carried out in their homes. The results of quantitative analysis showed that the male and female CAD patients in the youngest age group had the poorest HRQoL. Although, the patients average HRQoL improved on the dimensions of pain, energy and mobility, it deteriorated on the dimensions of social isolation, sleep and emotional reactions. From the viewpoint of methodological triangulation, the most significant finding was that the qualitative approach provided an explanation for the poor psychosocial HRQoL obtained by the quantitative approach, showing the crucial factor to be age and age-related aspects of the life situation. Interviews and the method of phenomenological psychology helped to gain insight into the informants’ situational experience of HROoL and life course, which was not detectable with a questionnaire.