2 In a certain noisy factory workers are provided with earpl

2.   In a certain noisy factory, workers are provided with earplugs and are expected to wear them. An industrial hygienist inspecting the plant found that 100 of the 500 workers in the factory were not wearing their earplugs because they regarded them as uncomfortable and as a nuisance. When all the workers are given a hearing test, it was found that 16 of the earplug wearers and 40 of the non-wearers had developed significant hearing loss. All had had normal hearing at their pre-employment examinations 4 years earlier, when the plant opened.

2.1. What was the annual risk of hearing loss associated with not wearing earplugs?    

      (2 points)

2.2. What was the annual risk of hearing loss in those who wore earplugs? (2 points)

Now, assume that the study was conducted as a cross-sectional study.

2.3. Create a two-by-two table using the information provided. Include an appropriate title, labels that identify each row and column, and row and column totals. (4 points)

2.4. Compare the odds for hearing loss in nonwearers compared with wearers of earplugs? (2 points)

2.5. What conclusion do you draw from this comparison? Explain your answer in a sentence or two. (2 points)

Solution