The aim of the study was to evaluate the suitability of the SF-12 questionnaire for the evaluation of the quality of life in 25-84-year-old inhabitants of Kaunas city and to compare quality of life between men and women as well as between socially and demographically different groups.
Material and methods: The study sample consisted of randomly selected inhabitants of Kaunas city, stratified by age and sex. The suitability of the questionnaire for the evaluation of the quality of life in the selected contingent was verified using Cronbach's alpha coefficient. The convergent validity of the questionnaire was assessed by the strength of the linear relationship between the domains of the questionnaire, calculating Pearson's correlation coefficients. We calculated mean ranges of the values of the questionnaire and compared the distribution of values.
Results: Cronbach's alpha values indicated a very strong internal consistency of the mental and physical domains of the SF-12 questionnaire (0.87 and 0.88, respectively). Women reported lower quality of life in the domains of mental health and physical health-pain as compared to men. People who were not living alone, with higher level of education, and employed reported better physical and mental health than those living alone, with lower level of education, or unemployed. In addition to that, people who were engaged in mental work during the study or had worked such work before reported better physical and mental health.
Conclusions: The questionnaire SF-12 is suitable for the evaluation of the quality of life in the population of Kaunas city. Women reported lower quality of life in mental health domain than men did. The evaluations of the quality of life worsened with increasing age and lower social and demographic status.