Rates, Ratios and Proportions

Know the difference between rates, ratios and proportions is very important. Match each option below with its descriptor.

28966 12 students in class contract food poisoning/100 students in class total

12 students in class contract food poisoning/100 students in class total

Proportion (Prevalence)

exact_answer none 28966 3162 margin of error +/-

75558 45 Asian males in a study/200 total males in the same study

45 Asian males in a study/200 total males in the same study

Rate

exact_answer none 75558 3357 margin of error +/-

24726 4 people develop arthritis in a study/732 person-months of follow-up time

4 people develop arthritis in a study/732 person-months of follow-up time

Ratio

exact_answer none 24726 6946 margin of error +/-

86203 45% of study participants are male/80% of study participants are non-smokers

45% of study participants are male/80% of study participants are non-smokers

Ratio of Rates (Rate Ratio)

exact_answer none 86203 8557 margin of error +/-

90248 (10 cases/100 person-months of follow-up)/(20 cases/1000 person-months of follow-up incidence)

(10 cases/100 person-months of follow-up)/(20 cases/1000 person-months of follow-up incidence)

Ratio of Proportions (Cumulative Incidence Ratio)

exact_answer none 90248 9997 margin of error +/-

95109 (5 new cases in Group 1/100 individuals in Group 1)/(20 new cases in Group 2/100 individuals in Group 2)

(5 new cases in Group 1/100 individuals in Group 1)/(20 new cases in Group 2/100 individuals in Group 2)

Use the information below to answer the following two-part question?

A study published in Archives of Internal Medicine (Trump, Hyams, Cross and Struewing, 1993) determined the current prevalence of tuberculin reactors among young adults entering the U.S. Navy. 2,214 male recruits were tested in January and February 1990; 55 tuberculin reactions.

Part I:

What was the overall prevalence of tuberculin reactors in the male Navy recruit population?

Enter your numeric answer into the field below; do not round your answer.

Part II:

Now, calculate the expected number of prevalent tuberculin reactors in the male Navy recruit population per 100 recruits.

Enter your numeric answer into the field below.