Abstract
After obtaining information from the National Health Insurance bills, comparative study of the relationship between air pollution and respiratory disease was made for two small areas in Tokyo; Kojiya as a highly polluted area of 6, 766 insurants and Hachioji as a contrast area of 8, 735 insurants. All the bills of above insurants demanded during 1971 were used. The result of comparison between Kojiya and Hachioji is as follows. The age adjusted incidence (average frequency of new consultation per person per year) of respiratory diseases of all kinds were higher in Kojiya for both sexes. Also the incidence of auricular diseases and injuries were higher in Kojiya, but those of skin and motor organs were the reverse. Among respiratory diseases, common cold in infants, bronchitis both acute and chronic in advanced ages and rhinitis in all ages were more frequent in Kojiya. Male were found to contract chronic bronchitis at earlier ages in Kojiya. It was also interesting to note that under 20 years of age, otitis media most of which must have the same source of infection as upper respiratory infection was more frequent in Kojiya.
Furthermore, biasses or inaccuracies bound to the bills were analyzed to confirm the reliability of the result and to discuss the limitation as a source of morbidity information.
