A quantitative analysis of the effects of age,period,and cohort in mortality of stomach cancer in Qixia County

Objective:To calculate the quantitative effects of ageperiodcohort in vital rates of gastric cancer mortality in Qixia county during 1970-1994.Methods:The mathematical model created by Kipper,and the regression coefficients of age,period and cohort were calculated by using triangle matrix.Results:The changing trend of gastric cancer mortality during the period time related to elder age groups(65-85 years old)and the five birth cohorts(from 1910-to 1890-).Conclusions:The trend of gastric cancer mortality in Qixia may be related to birth cohorts.