Question

U lilly WII Peceive a score of 0. Question 9 4 pts You conducted a study on the possible effects of air pollution on the development of chronic bronchitis. You examined a population of 9,000 men aged 45 years in January 2009. Of these, 6,000 lived in areas where they were exposed to air pollution and 3,000 did not. At this examination, 90 cases of chronic bronchitis were discovered, 60 among those exposed to air pollution. All the men initially examined who did not have chronic bronchitis were followed 5 years with repeated examinations. These examinations revealed 268 new cases of chronic bronchitis in the total group, with 30 among those unexposed to air pollution. What is the cumulative incidence (per 1000) of chronic bronchitis after 5 years among those exposed to air pollution? It is closest to...

Answer 1

9. Cumulative incidence rate = incidence of new cases during follow up / number of disease free cases at start of follow up

Total number of population - 9000

At the starting 90 cases of chronic bronchitis were found out of 9000

Means disease free = 9000-90

= 8910

In the follow up after 5 years , 268 new cases were found

Cumulative incidence = 268/ 8910 × 1000

= 3.007

11. Case fatality rate = number of deaths due to a specific disease /total number of persons with the specific disease × 100

Total number of persons with Tuberculosis - 300

Number of deaths due to tuberculosis - 60

Case fatality = 60/300 ×100

= 20%

Option A ) 20% is correct