Epidemiology: allocation concealment: 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: allocation concealment

Sample item

In a trial, a recruiter who knows the next allocation in a sequence enrols sicker patients into the new drug arm. Which safeguard was lacking?

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

The answer and the reasoning

B. Allocation concealment

Allocation concealment hides the upcoming assignment from those enrolling participants, such as through central randomisation or sealed opaque envelopes. Its absence permits selection bias at entry.

Option by option

  • A. Intention-to-treat analysis

    Intention-to-treat deals with analysis after the trial.

  • B. Allocation concealment (correct)

    Correct. Concealment prevents recruiters from steering patients.

  • C. Placebo control

    A placebo does not stop biased enrolment.

  • D. Double blinding

    Blinding acts after allocation, on participants and assessors.

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 B, Allocation concealment. Allocation concealment hides the upcoming assignment from those enrolling participants, such as through central randomisation or sealed opaque envelopes.

Why is "Intention-to-treat analysis" not the answer?

Intention-to-treat deals with analysis after the trial.

Why is "Placebo control" not the answer?

A placebo does not stop biased enrolment.

Why is "Double blinding" not the answer?

Blinding acts after allocation, on participants and assessors.

What concept does this question test?

It tests Epidemiology: allocation concealment in PSM. Its absence permits selection bias at entry.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. 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: allocation concealment?

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.