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.

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PSM · Epidemiology

Sample item

A researcher wants to control both known and unknown confounders when comparing two treatments. Which method at the design stage achieves this best?

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

The answer and the reasoning

A. Randomisation

Randomisation distributes known and unknown confounders equally among groups on average. Restriction and matching control only chosen known factors at the design stage, while stratification and multivariate analysis control known measured confounders at the analysis stage.

Option by option

  • A. Randomisation (correct)

    Correct. Only randomisation balances unknown confounders as well.

  • B. Stratified analysis

    Stratified analysis adjusts only for measured variables.

  • C. Multivariate analysis

    Multivariate analysis also adjusts only for measured variables.

  • D. Restriction

    Restriction limits a known factor but cannot address unknown confounders.

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, Randomisation. Randomisation distributes known and unknown confounders equally among groups on average.

Why is "Stratified analysis" not the answer?

Stratified analysis adjusts only for measured variables.

Why is "Multivariate analysis" not the answer?

Multivariate analysis also adjusts only for measured variables.

Why is "Restriction" not the answer?

Restriction limits a known factor but cannot address unknown confounders.

What concept does this question test?

It tests Epidemiology in PSM. Restriction and matching control only chosen known factors at the design stage, while stratification and multivariate analysis control known measured confounders at the analysis stage.

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.