death in this population. This provides another example of the effects of differing classification schemes. In the data from Machakos, Kenya, circulatory disease, TB and neoplasms were the three leading causes of death, together accounting for about 34% of dt-iths, although these data are for the age range 5 years and over, and so will include deaths in older children and the elderly. Data from the Ghana Health Assessment Project have been examined by restricting attention to those causes with an average age at death of 15 years or above. By multiplying the incidence rate by the case fatality rate for each cause, an estimate is obtained of the cause-specific mortality rate for adults. On this basis, circulatory diseases appear as the leading cause, followed by accidents and 'other diseases of the gastro-intestinal tract". It should be emphasised, however, that some childL.ood deaths and all deaths of old-age are included in these calculations, and the data are therefore not directly comparable with those from other studies. Note that in the data from Machakos and Senegal, circulatory diseases include both cardiovascular and cersbrovascular deaths, while these are shown separately for Madras and the Ghana Health Assessment Project. It is of interest that in Ghana, cerebrovascular deaths ranked second in importance, while they were relatively unimportant in Madras, and not among the ten leading causes.

The data published by Grosse (1980) show widely differing rankings of the leading causes of death in the four study areas (Table 6), but are difficult to interpret in the absence of detailed information on study methodology. The leading reported causes were enteric fever in the Punjab, maternal causes in E. Java, circulatory diseases in Eastern Region of Ghana, and TB in Terai, Nepal. The absence of any repcorted deaths from external,-causes, except in Nepal, is surprising, and in the case of Ghana conflicts markedly with the findings of the Ghana Health Assessment Project which indicated accidents to be the thiLi most important cause of adult death. The absence of deaths from neoplasms in all foul areas is also surprising, although it should be emphasised that these studies were restricted to the age range 15-44 years.

On the basis of the available data, only a number of general conclusions can be reached concerning the leading causes of adult death in developing countries. It seems clear that circulatory diseases and external causes are leading causes of adult death in nearly all the populations studied. There appear to be some interesting variations of detail, for example the very high rates of death from motor vehicle accidents in Lagos, Nigeria, and the large proportion of deaths from external causes that were attributed to suicide in the data from Madras, India especially among women. Other important causes that appear repeatedly are TB and neoplasms. Liver disease appeared especially important in some reports from Africa. Respiratory diseases and maternal causes were also important in some populations.

Morc striking, however, was the overall lack of information on causes of adult mortality, particularly in the developing countries of Sub-Saharan Africa and Asia, and especially in rural areas. Vital registration data for such populations are almost completely lacking, and very few special surveys have been conducted. Those which have been conducted have met difficult methodological problems, and are difficult 10