Question 1

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

Accepted Answer

To provide a set of methods for collecting, organizing, analyzing, and interpreting biomedical and healthcare data.

Question 2

A researcher wants to estimate the average blood pressure of adults in a city. She selects 200 adults at random from the city’s population of 50,000. In this context, what is the sample?

Accepted Answer

The 200 adults selected for the study.

Question 3

Which of the following is a key difference between descriptive and inferential statistics?

Accepted Answer

Descriptive statistics summarize data, while inferential statistics make predictions or decisions about a population based on a sample.

Question 4

Which sampling method involves dividing the population into groups with similar characteristics and then randomly sampling from each group?

Accepted Answer

Stratified random sampling

Question 5

A hospital wants to study patient satisfaction. They divide patients by department (e.g., cardiology, oncology, pediatrics) and randomly select patients from each department. What is the main advantage of this sampling method?

Accepted Answer

It ensures that all departments are represented in the sample.

Question 6

Which of the following is an example of a potential source of sampling bias?

Accepted Answer

Surveying only people who are easily accessible to the researcher.

Question 7

A researcher uses a list of all students at a university and selects every 10th student to participate in a study. What type of sampling is this?

Accepted Answer

Systematic sampling

Question 8

In a study, participants are randomly assigned to receive either a new medication or a placebo. What is the main purpose of randomization in this context?

Accepted Answer

To reduce bias and ensure groups are comparable.

Question 9

Which of the following best describes a cluster sampling method?

Accepted Answer

The population is divided into groups (clusters), and entire clusters are randomly selected for study.

Question 10

A study finds an association between smoking and low grades among college students. Which of the following is NOT a valid explanation for this association?

Accepted Answer

The association is due to the use of a true experimental design.

Question 11

Which of the following is a key step in the scientific method as applied to biostatistics research?

Accepted Answer

Randomly assigning participants to groups to avoid bias.

Question 12

Suppose you want to estimate the average height of students in a large university. Which sampling method would best ensure that your sample is representative of the entire student body?

Accepted Answer

Simple random sampling

Question 13

Which of the following statements about convenience sampling is TRUE?

Accepted Answer

It may lead to a sample that is not representative of the population.

Question 14

A researcher wants to study the effect of a new diet on cholesterol levels. She recruits participants from her local gym. What type of sampling is this, and what is a likely issue?

Accepted Answer

Convenience sampling; the sample may not be representative of the general population.

Question 15

Which of the following best describes the purpose of using a control group in an experimental design?

Accepted Answer

To provide a baseline for comparison with the treatment group.

Question 16

In a stratified random sample, how is the sample size from each stratum typically determined when using proportional allocation?

Accepted Answer

The sample size from each stratum is proportional to the stratum's size in the population.

Question 17

Which of the following is an example of response bias in a survey?

Accepted Answer

Participants answer questions in a way they think is socially acceptable rather than truthfully.

Question 18

A researcher uses a multistage sampling method to select participants for a national health survey. Which of the following best describes this approach?

Accepted Answer

Sampling is conducted in multiple stages, often combining different sampling methods at each stage.

Question 19

Which of the following formulas represents the calculation of the sampling interval $$k in $$systematic sampling, given a population size $$N$$ and desired sample size $$n$$?

Accepted Answer

$$k = \frac{N}{n}$$

Question 20

A study uses laboratory tests to collect data on blood glucose levels from participants. Which type of data collection method is this?

Accepted Answer

Objective measurement

Module 1: Introduction to Biostatistics – Key Concepts and Sampling Strategies

Guida di studio - Domande di pratica

Study guide - Flashcard