[Effect of the selection of reference population on the evaluation of the degree of the risk of death among industrial cohorts].

The report is devoted to one of the main problems of studies on death rate in industrial cohorts. In the study on cohort consisting of workers of asbestos processing plant in Lodz, the general population of Poland was selected as a reference population. Such method of analysis was used chiefly due to the fact that the data for local population of the Lodz district were unavailable. The report presents a comparative analysis of mortality based on the standardized death rate calculated for the total Polish and the Lodz district populations for the period for which appropriate data were available (1974-1985). The conclusions resulting from both analyses point to overmortality due to some selected causes regardless which reference population was taken into consideration although absolute number of these surpluses depends on selection of reference population.