$$p = P(\text{observed result} \mid \text{null hypothesis is true})$$

Question 1

Which of the following best describes the role of biostatistics in public health research?

Accepted Answer

It translates data and numbers into usable information to identify cause and effect, health risks, and cost effectiveness.

Question 2

A researcher finds a p-value of $$p = 0.03$$ when comparing two treatments for diabetes. What does this result indicate?

Accepted Answer

There is a 3% chance that the observed difference is due to random chance, and the result is statistically significant.

Question 3

Which statistical test would be most appropriate to determine if there is a significant difference in smoking rates between males and females?

Accepted Answer

Chi-Squared Test

Question 4

In a screening test for a rare disease, which is more important: sensitivity or specificity? Why?

Accepted Answer

Sensitivity, because it reduces the number of false negatives and ensures most cases are detected.

Question 5

A confidence interval of 95% means:

Accepted Answer

There is a 95% probability that the true parameter lies within the interval.

Question 6

If a study reports a p-value of $$p = 0.08$$, what is the correct interpretation?

Accepted Answer

The result is not statistically significant at the $$\alpha = 0.05$$ level.

Question 7

Which of the following is an example of categorical data?

Accepted Answer

Yes/No responses to a survey question

Question 8

A hospital wants to compare the average age of patients in three different departments. Which statistical test should they use?

Accepted Answer

ANOVA

Question 9

What is the main difference between descriptive and inferential statistics?

Accepted Answer

Descriptive statistics summarize data; inferential statistics make predictions or inferences about a population based on a sample.

Question 10

Which of the following would increase the statistical power of a study?

Accepted Answer

Increasing the sample size

Question 11

A false positive in a medical test means:

Accepted Answer

The test indicates a disease is present when it is not.

Question 12

Which formula represents the calculation of a p-value in hypothesis testing?

Accepted Answer

$$p = P(	ext{observed result} \mid 	ext{null hypothesis is true})$$

Question 13

In cost-benefit analysis, which of the following is typically more difficult to calculate?

Accepted Answer

The monetary value of the benefit, such as a life saved

Question 14

A researcher wants to know if age, exercise level, and self-esteem are related to weight status. Which statistical method should be used?

Accepted Answer

Multiple Regression

Question 15

Which of the following best describes lead-time bias in screening tests?

Accepted Answer

It occurs when earlier detection of a disease falsely appears to improve survival time, even if the outcome is unchanged.

Question 16

Which of the following is a continuous variable?

Accepted Answer

Blood pressure measured in mmHg

Question 17

If a screening test has high specificity, what does this mean?

Accepted Answer

It correctly identifies most people who do not have the disease (few false positives).

Question 18

Which of the following is an example of inferential statistics?

Accepted Answer

Using a sample to estimate the average height of all adults in a country

Question 19

A study finds that the p-value for the relationship between exercise and heart disease is $$p = 0.01. $$What does this mean?

Accepted Answer

There is strong evidence that exercise and heart disease are related.

Question 20

Which of the following best describes risk perception?

Accepted Answer

It involves psychological factors and is often irrational compared to expert estimates.

Statistics and Biostatistics in General Biology: Concepts, Applications, and Analysis

Study Guide - Practice Questions