Biostatistics: binomial distribution: 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 · Biostatistics: binomial distribution

Sample item

Ten patients receive the same drug, each with the same independent probability of responding, and the number who respond is counted. Which distribution describes this count?

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

The answer and the reasoning

A. Binomial distribution

The binomial distribution applies when there are a fixed number of independent trials, two possible outcomes for each, and a constant probability of success. The Poisson distribution is used when events are rare and there is no fixed number of trials. The other two are sampling distributions for test statistics.

Option by option

  • A. Binomial distribution (correct)

    Correct. A fixed number of independent trials with a constant response probability is binomial.

  • B. Poisson distribution

    The Poisson distribution has no fixed number of trials and is meant for rare events.

  • C. Chi-square distribution

    The chi-square distribution is a test statistic distribution, not a model for counts of responders.

  • D. Student's t distribution

    The t distribution is for sample means and not for counts of successes.

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, Binomial distribution. The binomial distribution applies when there are a fixed number of independent trials, two possible outcomes for each, and a constant probability of success.

Why is "Poisson distribution" not the answer?

The Poisson distribution has no fixed number of trials and is meant for rare events.

Why is "Chi-square distribution" not the answer?

The chi-square distribution is a test statistic distribution, not a model for counts of responders.

Why is "Student's t distribution" not the answer?

The t distribution is for sample means and not for counts of successes.

What concept does this question test?

It tests Biostatistics: binomial distribution in PSM. The Poisson distribution is used when events are rare and there is no fixed number of trials. The other two are sampling distributions for test statistics.

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 Biostatistics: binomial distribution?

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.