Health impact assessment is an internationally recognized tool for informed decision-making. The authors participated in building statistical models for assessing the health effects of decisions made inside and outside the health sector. They used logistic regression to investigate the role of individual factors like gender, age, education and economic activity determining the all-cause mortality and diseases of circulatory system and neoplasm as well. The results of statistical modelling proved that gender, education and economic activity modify the effect of age on mortality in multiple interactions. Since several factors have impact simultaneously on mortality, modifying the others' effects, analyzing these associations only by use of multivariate statistical methods is an adequate approach. Models presented in this article can be starting points for investigations exploring the effects of multiple health-determinants and researches in which also social-economic determinants are included in health impact assessment.