Social class differences in mortality from diseases amenable to medical intervention in New Zealand.

Social class differences in mortality from causes of death amenable to medical intervention were examined. All deaths in New Zealand males aged 15-64 years during the periods 1975-1977 and 1985-1987 were identified. Strong social class gradients in mortality from causes of death amenable to medical intervention were observed during both periods. Furthermore, social class inequalities were more pronounced for amenable causes of mortality than for non-amenable causes. However, a marked decline in the age-standardized mortality rate from amenable causes was observed, with the rate falling by 30% over the 10-year study period. This decline was twice as large as the drop in the non-amenable mortality rate. Despite the fall in the death rate from amenable causes, social class inequalities in mortality persisted among New Zealand men, with the lowest socioeconomic group experiencing a death rate from amenable causes of mortality that was 3.5 times higher than men in the highest socioeconomic group.