Cohort study of opportunity for selection on two Swedish 19th century parishes with a survey of other estimates.

Two Swedish parishes, Fleninge in the county of Malmöhus and Nedertorneå in the county of Norrbotten, have been compared for differences in opportunity for selection. The material has consisted of demographic data from the 19th century. Both components of the index, estimated from mortality and fertility differences respectively, are high in comparison to other available estimates, and the index for Nedertorneå is higher than that of Fleninge.