Epidemiology: practice question

A PSM question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

PSM · Epidemiology

Sample item

What does incidence measure in a defined population over a stated period?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

A. New cases occurring during that period

Incidence measures the occurrence of new cases over time among a population at risk, making it useful for studying disease risk and the impact of preventive interventions.

Option by option

  • A. New cases occurring during that period (correct)

    Correct: incidence counts new disease events over a specified period.

  • B. All existing cases at one point

    All existing cases describe prevalence rather than incidence.

  • C. Deaths from all causes only

    All-cause deaths describe mortality, not incidence.

  • D. Average duration of illness only

    Illness duration influences prevalence but is not itself incidence.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More PSM questions

Questions about this PSM question

What is the answer to this PSM question?

The best answer is A, New cases occurring during that period. Incidence measures the occurrence of new cases over time among a population at risk, making it useful for studying disease risk and the impact of preventive interventions.

Why is "All existing cases at one point" not the answer?

All existing cases describe prevalence rather than incidence.

Why is "Deaths from all causes only" not the answer?

All-cause deaths describe mortality, not incidence.

Why is "Average duration of illness only" not the answer?

Illness duration influences prevalence but is not itself incidence.

What concept does this question test?

It tests Epidemiology in PSM. The correct option holds because: Correct: incidence counts new disease events over a specified period.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Epidemiology?

Practise biostatistics with small calculations until sensitivity, predictive values and risk measures are automatic. Then use the flashcards and the other PSM questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.