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

Exercise 5

How does the "healthy worker effect" influence the interpretation of findings from occupational health research? An epidemiologic researcher finds that mortality for assembly line workers in an automobile factory is slightly higher than the mortality of the general population. Assume that the healthy worker effect is operative. Would it tend to decrease or increase mortality differences between the workers and the general population?