title: A mathematical model relating cohort and period mortality.
abstract: This paper presents a mathematical model for changing mortality in functional form. This model may be used to obtain cohort forces of mortality and cohort survivorship functions from a period force of mortality and a period life table under conditions of gradually changing mortality if an estimate of the amount of change in mortality is available. An example is given to show how the cohort functions are derived from the period functions.
mesh_terms: D000367:Age Factors; D006801:Humans; D008433:Mathematics; D008962:Models, Theoretical; D009026:Mortality; D013997:Time Factors