OBJECTIVES: Demographic factors such as age, gender or cultural factors may influence the utility value of health states and interact with health domain impact on utility. The aim of this analysis is to identify factors influencing utility values of EQ-5D and to estimate the relationships between additional variables and utility.  METHODS: Data from study valuating EQ-5D with time trade-off for Polish population were used to evaluate influence of demographic, social and cultural factors on EQ-5D utility value. Based on additional data concerning demographic and lifestyle factors collected, adjusted modeling was performed using GRETL and WinBugs software. Impact of this factors was analyzed by directly including variables in the model, as well as adjusting for variables corresponding interaction between the factors and health domain. RESULTS: Data from 230 interviews (5280 valuations) were analyzed. Preliminary random effects model  was developed, with constant and N3 factor, all coefficients statistically significant, R2 equal to 0.37 and value -0.647 for 33,333 health state. After adjusting base model for gender and smoking no influence on utility value was observed. Including the interaction terms between age (0-1 variable defined as above/below median of 38 years) and belief in life after death (defined as strong agreement) with health domains (level 3) proved to be statistically significant and improved model R2 up to 0.40. Direct influence of belief in life after death on the utility value of health states was significant,  R2 equal to 0.38 and coefficient value 0.16. CONCLUSIONS: Demographic and cultural factors influence the utility value of health in Polish population. According to results based on preliminary data belief in life after death significantly reduces utility loss.