Community Medicine Practice

20 learning units • 10 questions per unit • 200 explained questions

Module 04 — Biostatistics, Sampling & Data Presentation

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Question 01 • Single best answer

Which summary is often preferable for a strongly right-skewed income distribution?

A. Mean alone without spread B. Mode alone for every purpose C. Standard error as the income value D. Median with interquartile range

Question 02 • Single best answer

Blood group is which type of variable?

A. Continuous numerical B. Nominal categorical C. Ordered interval scale D. Person-time rate

Question 03 • Single best answer

What does standard deviation primarily describe?

A. Variation among observations B. Probability the null is true C. Number of missing records D. Guaranteed causal effect

Question 04 • Single best answer

What does the standard error of a mean primarily describe?

A. Biological variation of every individual B. A systematic recording mistake C. The full observed range D. Sampling precision of the estimated mean

Question 05 • Single best answer

For independent observations, quadrupling sample size changes the mean standard error how, if spread is unchanged?

A. It doubles B. It quadruples C. It halves D. It becomes exactly zero

Question 06 • Single best answer

Which interpretation of p = 0.03 is correct?

A. The null hypothesis has a 3% probability of being true B. The treatment benefits exactly 97% of people C. It quantifies data incompatibility with the specified null model D. The observed effect is necessarily important

Question 07 • Single best answer

Why must cluster sampling be considered during analysis?

A. Clusters always guarantee independent observations B. Observations within clusters can be correlated C. Cluster sampling removes all uncertainty D. Each cluster is necessarily the same size

Question 08 • Single best answer

A survey excludes all remote villages from its frame. What will a larger urban sample fail to fix?

A. Random precision B. Coverage bias C. Number of completed interviews D. Availability of urban observations

Question 09 • Single best answer

Which graph best displays the distribution of a continuous measurement?

A. Pie chart of participant names B. Unlabeled decorative icon C. Histogram D. Flowchart of staff roles

Question 10 • Single best answer

Why should repeated measurements on the same patients not be treated as unrelated samples?

A. Their observations are paired or correlated B. Their values must be identical C. Repeated measurements eliminate variation D. Pairing makes all tests impossible