Question

Investigators conducting a study regarding the effects of water pollution and peptic ulcer disease obtained the following data: A population of 9000 men and women, aged 45, were examined on January 1, 1985. Of these people, 6000 were exposed to toxins in the local water supply and 3000 were not. At the time of this exam, 90 cases of peptic ulcer disease were discovered; 60 of these cases were among those exposed to toxins in their local water. All the people at the initial exam who were free from peptic ulcer disease were followed with repeat exams over the following year. This study revealed 268 new cases in the total group; of these, 238 cases were among those exposed to toxins in their local water. A. Calculate the prevalence per 1000 people of peptic ulcer disease on January 1, 1986: Among the exposed Among the unexposed B. Calculate the 1985 incidence rate/1000 people of peptic ulcer disease: Among the exposed Among the non exposed

Answer 1

The prevalence per 1000 people of peptic ulcer disease on January 1, 1986 was 0.01 for both the exposed and unexposed group. The 1985 incidence rate/1000 people of peptic ulcer disease was 0.015 for the exposed group and 0 for the non-exposed group.

Step-by-step explanation:

To calculate the prevalence per 1000 people of peptic ulcer disease on January 1, 1986:

1. Among the exposed: 60 cases out of 6000 exposed people = prevalence of 0.01
2. Among the unexposed: 30 cases out of 3000 unexposed people = prevalence of 0.01

To calculate the 1985 incidence rate/1000 people of peptic ulcer disease:

1. Among the exposed: 90 cases out of 6000 exposed people = incidence rate of 0.015
2. Among the non-exposed: 0 cases out of 3000 non-exposed people = incidence rate of 0

Answer 2

Kindly check explanation

Step-by-step explanation:

The prevalence per 1000 among the exposed :

Total number of diseases among those exposed = 60 + 238 = 298

Prevalence per 1000 among the exposed :

(298 / 9000) * 1000 = 33.11

Prevalence per 1000 among the non exposed :

((90 - 60) + (268 - 238)) / 3000

(60 / 3000) * 1000 = 20

Incidence rate per 1000 among the exposed :

238 / 5940 * 1000

0.0400673 * 1000 = 40.07

Incidence rate per 1000 among the unexposed :

((90 - 30) / (3000-30)) * 1000

(60/2970) * 1000 = 20.2