This study aims at identifying determinants of health related quality of life in Poland, and in particular at verifying whether health domains are complements or substitutes and what the impact of heterogeneity of population on the health state valuation is. The paper uses data in panel structure coming from a survey conducted in Poland and consisting of 6700 valuations (after data cleaning) of EQ-5D health states with time trade-off method. Several econometric models are built in order to detect the impact of complementarity and heterogeneity. Random effects models as well as random parameters models estimated using Bayesian approach are used. The results show that health domains are complementary goods. Especially the lack of pain/discomfort is a complement to other health domains. Demographic factors influence how health state change impacts utility. These factors encompass sex, education, respondent’s health state and even belief in life after death.

Background: Due to current increased life expectancy, the quality of life (QoL) of senior patients is gaining in importance. The aims of this study were: to estimate QoL in a group of patients, aged above 64 years, that is cared for by general practitioners (GPs) in Krakow, Poland, and to find relation-ships between elements of QoL and the results of comprehensive geriatric assessment (CGA) and other important medical and social factors.
Methods: We designed a cross-sectional, questionnaire study among patients who attended GPs’ sur-geries from April 2018 to April 2019. To examine the patients, we used the Euro-Quality of Life Ques-tionnaire (EQ-5D-5L) and eight scales forming CGA: the Activities of Daily Living, the Instrumental Activities of Daily Living, Mini-Mental State Examination, Geriatric Depression Scale, Timed Up and Go Test, Mini Nutritional Assessment, Clinical Frailty Scale and Athens Insomnia Scale.
Results: The lowest QoL was observed in dimensions of pain/discomfort and mobility, where 70% and 52% of patients, respectively, reported problems in these areas. Only 91 (21%) respondents had highest results in all five dimensions of QoL. The average score in the Visual Analogue Scale (VAS) of the EQ-5D- 5L (representing self-rated health on a given day) was 62.36 ± 18.98 points. Statistically significant relationships were observed between QoL and age, physical activity and multimorbidity (in all cases p <0.001). The results of QoL were correlated with every aspect of CGA, while the strongest relationship was noticed between scores in the EQ-5D-5L VAS scale and scales assessing depression and frailty (p <0.001; r = –0.57 both).
Conclusions: Our study showed that in senior patients in Krakow QoL was relatively high. Seniors mostly complained of pain/discomfort and problems with mobility. Moreover, dimensions of QoL were connected with the results of CGA. During visits, GPs should specifically question patients about the above mentioned aspects of QoL.