Biostatistics: mean and median: 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: mean and median

Sample item

Which measure of central tendency is generally preferred for highly skewed income data?

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

The answer and the reasoning

C. Median

The median is less affected by extreme values than the mean and better represents the center of a skewed distribution. Dispersion should also be reported appropriately, often with an interquartile range.

Option by option

  • A. Standard deviation

    Standard deviation measures spread rather than central tendency.

  • B. Arithmetic mean only

    The mean can be pulled strongly by very high incomes.

  • C. Median (correct)

    Correct. Median is robust to outliers and skew.

  • D. Range only

    Range is highly sensitive to extreme values and is not a central measure.

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 C, Median. The median is less affected by extreme values than the mean and better represents the center of a skewed distribution.

Why is "Standard deviation" not the answer?

Standard deviation measures spread rather than central tendency.

Why is "Arithmetic mean only" not the answer?

The mean can be pulled strongly by very high incomes.

Why is "Range only" not the answer?

Range is highly sensitive to extreme values and is not a central measure.

What concept does this question test?

It tests Biostatistics: mean and median in PSM. Dispersion should also be reported appropriately, often with an interquartile range.

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: mean and median?

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.