The purpose of the study was to establish the rate of emigration in a random selection of villages, with a view to forecast the likely loss of population in a follow up study on BCG vaccination in the area. The study was carried out in the total population belonging to 35 villages of Channapatna, Devanahalli, Magadi and Nelamangala taluks of Bangalore district in April 1960. Demographic characteristics such as birth and death rates, immigration rates and proportion of persons temporarily absent, were also studied. The head of the household if absent, any other responsible adult was interviewed on a house to house basis, regarding the composition of the family, according to the National TB Institute manual for census takers. Estimation of migration was to be based on the registered population of the current day, the population exactly one year ago and all relevant events during the intervening year.

The thirty five villages surveyed were found to have a population of 13,838 persons at the time of interview. This figure includes: (A) 13138 persons in the household at the time of census taking also belonged to it one year ago. (B) 470 persons born during the past year. (C) 230 persons immigrated during the past year. (D) 200 persons dead during the past year. (E) 307 persons emigrated during the past year & (F) 770 persons temporarily absent. The net increase in the population from April 1959 to April 1960 was, 193 persons or 14 per thousand.

It was estimated that not more than 5% of the population would be lost by emigration over a period of two years. About 1/3rd of the emigration is within the same taluk. Only a small portion of the emigrants are above 30 years of age. It is also found that a good proportion of women's migration is due to marriage. The study findings revealed that the hypothesis that large number of people leave the village every year, making BCG coverage impossible could hardly be upheld.