| The mortality decline in the more developed nations has been related to three factors: a reduction in exposure to disease, improved nutrition, and medical measures. The contribution of medical measures has been a source of continuing controversy. This contribution has been examined using one of two basic approaches. The first, referred to as the period approach, arranges the mortality data by calendar year, while the second, the cohort approach, arranges the data by birth cohort. In the present analysis, the two approaches are combined in an age, period, cohort model to examine disease-specific mortality patterns for England and Wales since 1861 and New Zealand and Italy since 1881. Using this model of mortality, it is concluded that medical measures introduced after 1935 may have had a larger impact than was formerly realized. |
