Among uranium mine workers, 60 lung cancer deaths are observed over 10 years. Using national age-specific lung cancer mortality rates applied to the workers' age distribution, 40 deaths were expected. The Standardized Mortality Ratio is:

• A 67 and lower than expected mortality
• B 100 and equal to expected mortality
• C 150 and 50% excess mortality ✓
• D 240 and 140% excess mortality

Explanation

SMR equals observed deaths divided by expected deaths multiplied by 100: 60 divided by 40 times 100 gives 150, meaning a 50% excess compared with the general population. Indirect standardization is chosen precisely because age-specific rates for the worker population itself are not required, only the expected count derived from reference rates. An SMR of 100 indicates parity and 67 would imply fewer deaths than expected.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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