Measures of Central Tendency & Dispersion MCQ Quiz | Biostatistics

Welcome to this Biostatistics quiz designed specifically for MBBS students. This module focuses on the fundamental concepts of Measures of Central Tendency and Dispersion, which are critical for interpreting clinical data and research papers. This quiz contains 25 multiple-choice questions that will test your understanding of mean, median, mode, standard deviation, variance, and their applications in medical science. A strong grasp of these topics is essential for evidence-based practice. After submitting your answers, you will receive your score and a detailed review of each question. For your convenience and future revision, you can also download all the questions along with their correct answers in a PDF format. Good luck!

1. Which measure of central tendency is most affected by extreme values (outliers)?

2. In a perfectly symmetrical (normal) distribution, what is the relationship between the mean, median, and mode?

3. The blood pressure readings of a group of patients are an example of which type of data?

4. Which measure of dispersion is calculated as the square root of the variance?

5. The middle 50% of the observations in a dataset are bounded by:

6. In a right-skewed (positively skewed) distribution, which of the following is the correct order of the central tendency measures?

7. The standard error of the mean (SEM) measures:

8. A researcher wants to compare the variability of cholesterol levels (mg/dL) and body weight (kg) in a group of patients. Which measure is most appropriate for this comparison?

9. The 50th percentile is equivalent to which measure of central tendency?

10. In a normal distribution, approximately what percentage of observations fall within one standard deviation of the mean (μ ± 1σ)?

11. If the variance of a dataset is 25, what is the standard deviation?

12. For a dataset of patient ages, which is the most appropriate measure of central tendency if the data is highly skewed due to a few very old patients?

13. The sum of deviations of individual values from their arithmetic mean is always:

14. Which of the following is a measure of dispersion, not central tendency?

15. The mode is the best measure of central tendency for which type of data?

16. If a dataset of fasting blood sugar has a mean of 110 mg/dL and a standard deviation of 15 mg/dL, what is the Z-score for a patient with a reading of 140 mg/dL?

17. A bimodal distribution is characterized by having:

18. The range is a simple measure of dispersion but is limited because it:

19. In a left-skewed (negatively skewed) distribution of patient recovery times, which statement is true?

20. Which of the following is NOT a property of the standard deviation?

21. A sample has a mean of 50 and a standard deviation of 10. According to Chebyshev’s theorem, at least what percentage of the data lies between 30 and 70?

22. If you add a constant value of 5 to every observation in a dataset, how does the standard deviation change?

23. In a box-and-whisker plot, the length of the box represents which measure of dispersion?

24. What is the median of the following dataset: 7, 3, 9, 5, 2?

25. As sample size (n) increases, the Standard Error of the Mean (SEM) will: