Document jmLEmmO9ZaXpQY0DNJKgnz1ZQ

32 TABLE 5 Part III Study o( Combined Cohorts Combined death rates per 100,000 man-years of risk for Asbestos and THctford Mines "Proved" cancer of lung death rate1 per 100,000 man-years of risk 25.S { 9 35271.5 "Suspected" plus proved cancer of lung death rate per 100,000 man years of risk a 34,0 ( 12 . 35271.5 In two, no autopsy was performed but the clinical signs and symptoms were such that the death certificates read "cancer of the Lung", and "suspected lung cancer". The third case came to au topsy but there was a-dliference of opinion between two pathologists as to whether lung cancer was present. The term "man-years of risk" has been used to mean the number of men at risk for the year under observation. An individual who lived throughout the year was counted as a full man-year of risk, but one who died during the year was counted as one-half a man-year. Deaths occurring in these two cohorts, and In which lung cancer is considered to have been proved as a cause, are shown In tabulated form on the next page. Also shown are three deaths in the Thetford Mines cohort which have been considered as "suspected" lung cancer cases