Document 3eEQRJX7zjKdanRxXKBxXVz10

16. check upon the Information obtained from tba clinical record* ol/thlt group, lit record* of the life Insurance company were examined for all death clalme paid under tho policy, and particular notice wna taken of the claim* In which the proof of death wa* baaed on cancer of the lung. Death* from lung cancer among aabealos miner* were thu* deter mined from the clinical record* In tho medical (ervlco of the industry and checked by mean* of tha death certificate* and Insurance company record*. The death* were then verified Individually by reviewing them with the physician* In charge of tho medical services. In thla manner, there was established a list of cases in which primary cancer of the lung t* considered to have been provod a* the cause of death. A few casee In which lung caneer la atrongly luspacted but not proved a* the cauae of death wore coneldered eeparately. Mortality rateo have been calculated using both tho "proved" and tho total of "provod" and "suspected" cases during the years under observation. Comparlson* ware then made belweon the death ratos from the same cause among specific tegmenta of unexpoecd person*. Ail lung cancer deaths, both sus pected and proved, were carefully analysed to determine possible relation ship or correlations botween the development of lung cancer and any factor known from the clinical record* such * family history of cancer, personal history of heavy smoking, coexlotenco of aebostosls, or exposure to aebssto*. In addition to this analysis of deaths occurring In the cohort and during the years under observation, every known death from cancer of the lung, as well ss every case diagnosed but still living, has been.tabulated and 0266