The study analysed the mortality rates (obtained from death certificates and census returns contained in the Decennial Supplement on Occupation and Mortality) in England and Wales during 1970-1972, by occupation and social class. Mortality rates were calculated in terms of the standardized mortality ratio (SMR):

(SMR =observed deaths X 100)
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                expected deaths

A major finding of the study was that mortality was inversely related to social class. This result may be explained in two ways. Either the incidence of TB was greater in the lower classes or, there was a significant difference in case fatality between the classes. Based on the available information, it was concluded that there were good reasons to suppose that both explanations were important.

The aim of the sample survey conducted in January-February 1968 in the railway colonies of West Bengal was to determine the "Sociological Tuberculogenic Factors" that were responsible for the development and spread of TB in the population. The sample studied was found to be representative of the general population. The trend and behaviour of disease was dependent on the relevant standard of living (separate colonies were built for officers, upper subordinates and other categories with wide difference in social conditions), working conditions, habits and social evils such as alcohol consumption and "ganja" (illicit drug) smoking. The incidence of disease was more rampant amongst the low-paid categories and was inversely related to the group's income. Based on the findings, some suggestions were made to check the progress and spread of TB.

The decline of mortality in the more developed nations has been related to two major influences, economic development and the introduction of medical measures. The contribution of medical measures has been a source of continuing controversy. Most previous studies employed either a birth cohort or calendar year arrangement of mortality data to address this controversy. The present study applies an age-period-cohort model to mortality from respiratory TB in England & Wales, Italy, and New Zealand, in an attempt to separate economic influences from that of medical measures. The results of the analysis indicate that while the overall contribution of medical measures is small, when examined by calendar year, specific birth cohorts both in Italy and England and Wales benefited substantially from these measures. The environmental conditions in New Zealand, however, were such that the introduction of medical measures barely affected declining mortality levels from respiratory TB.

Since there has been an association between TB, poverty and over-crowding, most observers assumed that during pre chemotherepeutic era, decline in mortality due to TB has been because of the improvement in social conditions alone. As per the records available from 1850, except during the world wars, mortality from TB has steadily declined. However, the possible effects of natural immunity acquired by successive generations in a process of natural selection and selective mortality of susceptible individuals or family are over looked in studies of historical TB rates. The aim of this study is to reinvestigate the association between changes in mortality from TB on the one hand and mortality from other poverty related diseases, socio-economic conditions and measures in Victorian England on the other. Mortality statistics for England and Wales from 1853 to 1910 (before world war) were obtained from the Registrar General Annual Reports. These publications included data on TB, cholera and dysentery. Infant mortality, total mortality rates, socio-economic measures, statistics on average real earnings were also taken from the same source. Data on other diseases over the same period of time were not as complete, hence not included for the comparison.

The results showed total mortality rates declined by 0.80 per year where as TB mortality declined by 1.71. The average annual declining for TB was therefore twice that for all causes. The infant mortality a closer indicator of improvement in social deprivation declined even more slowly by 0.58 per year. Secondly, while TB deaths showed a steadily improving trend over the 60 years, infant mortality improved only from 1900. The study showed that TB mortality declined at a much faster rate than any indicator of social deprivation improved for the period 1853 to 1910. It is therefore unlikely that social improvements alone were responsible for the remarkable steady decline in TB mortality. Other diseases such as diphtheria and cholera thought to be poverty related showed no similar decline. The decline in TB mortality far exceeded improvements in social conditions and other disease markers of poverty. Some other factors are likely therefore do have been playing a part, of which the most important is probably the process of natural selection.

Adverse social conditions and social habits are significant as a cause of illness because of their power to disable. Chronic infections like TB present some of the most serious medical social problems put a heavy emotional strain on the patient. A TB control programme can be effective when the causal factors in adverse social conditions such as poverty, undernourishment and social habits are removed. The medical social worker, by working with the doctor and helping to co-ordinate services of the social and health agencies, can play an important role in the control of TB.