Much discussion has taken place regarding possible health hazards from exposure to anesthetic gases. In one study 525 Michigan nurse anesthetists were analyzed by mail questionnaires and telephone interviews in 1972 to find incidence rate of cancer [9]. Of this group, seven women reported having the new malignancy other than skin cancer during 1971.
i) Determine best estimate of 1971 incidence rate from these data?
ii) Give the 95% CI for true incidence rate.