Epidemiology for Public Health Practice 5th Edition by Robert Friis,Thomas Sellers

Exercise 9

The association between job-related exposure to welding fumes and chronic obstructive pulmonary disease (COPD) was explored in a case-control study. The following data were reported for 399 COPD patients: 37 currently employed as welders; the remainder had no occupational exposure. Among 800 controls, 48 were employed as welders. Set up a 2 by 2 table and calculate the OR.