Reklaitiene R et al. - The definite upward period effect was observed from 1990 to 1994 both among men and women, and was followed by a sharp fall during 2000–2004. Cohort and period effects have contained relevant information that partially explained trends in stroke mortality among 25–64 year-olds in the Lithuanian urban population. The Poisson regression models could be applied for the examination and explanation of the different causes of the population mortality.