ATI RN
Foundational Public Health Services Questions
Question 1 of 5
In a given calendar year there were 100 cases of X disease in a city of 500,000 inhabitants. Half of the patients died. All the cases occurred in the same city district. Given the circumstances, what else do we have to know to calculate the incidence rate in this district and year?
Correct Answer: C
Rationale: Incidence rate = (new cases / population at risk) x constant; we need the district’s population, not the city’s total.
Question 2 of 5
When calculating the incidence rate for a given disease the numerator of the fraction denotes:
Correct Answer: C
Rationale: Incidence rate = (new cases / population) x constant, focusing on new occurrences.
Question 3 of 5
Let us assume that a new screening test was prepared to detect ovarian cancer. The chart below shows the frequency of its results. Which of the following is true if we take as a referential value the result of 0-30 µg/dL ?
Correct Answer: C
Rationale: Without a chart, assuming a typical test, a cutoff like 0-30 µg/dL implies some overlap, leading to false positives among healthy women.
Question 4 of 5
Morbidity rate reaches higher values if:
Correct Answer: B
Rationale: Morbidity (prevalence) increases with longer disease duration as more cases accumulate.
Question 5 of 5
In the formula for calculating the specificity of the test, the following number of results is entered in the numerator of the fraction:
Correct Answer: A
Rationale: Specificity = TN / (TN + FP), with true negatives in the numerator.