PCB Research & Evidence-Based Practice 5

Question 1

Which of the following best describes a 'type I error' in hypothesis testing?

Accepted Answer

Incorrectly concluding that an effect exists when it does not (false positive)

Answer

A Type I error (alpha error) occurs when a researcher rejects a true null hypothesis, concluding there is an effect when none actually exists.

Question 2

A practitioner uses 'PICO' format to structure a clinical question. What does the 'C' in PICO stand for?

Accepted Answer

Comparison or control intervention

Answer

In PICO, C stands for Comparison — the alternative intervention or control condition against which the primary intervention is evaluated.

Question 3

Which sampling method gives every member of the target population an equal chance of being selected for a study?

Accepted Answer

Simple random sampling

Answer

Simple random sampling assigns each population member an equal probability of selection, minimizing selection bias and supporting external validity.

Question 4

When a systematic review uses meta-analytic techniques, the 'forest plot' visually displays which information?

Accepted Answer

Effect sizes and confidence intervals for each included study and the pooled estimate

Answer

A forest plot shows each study's effect size with its confidence interval as a horizontal line, plus a diamond representing the pooled meta-analytic estimate.

Question 5

A practitioner notices that participants in a study improved simply because they knew they were being observed, not because of the intervention itself. This phenomenon is called:

Accepted Answer

Hawthorne effect

Answer

The Hawthorne effect describes behavior change resulting from awareness of being observed rather than from the experimental intervention.

PCB - Design Practice Test

PCB - Design Practice Test

PCB Research & Evidence-Based Practice 5