ATI RN
Questions in Epidemiology Questions
Question 1 of 5
What type of study design is best suited for studying the natural history of a disease?
Correct Answer: C
Rationale: Cohort studies (C) follow disease progression over time (e.g., HIV stages). A is snapshot, B is retrospective, D is interventional.
Question 2 of 5
What type of bias occurs when the measurement of exposure or outcome is influenced by the knowledge of the hypothesis?
Correct Answer: D
Rationale: Observer bias (D) arises when hypothesis knowledge skews measurement (e.g., biased scoring). A is selection, B is broad, C is recall-specific.
Question 3 of 5
Which of the following is an example of selection bias?
Correct Answer: A
Rationale: Loss to follow-up (A) is selection bias if related to exposure-outcome (e.g., sicker patients leaving). B, C, and D are information biases.
Question 4 of 5
Specificity of a diagnostic test is defined as:
Correct Answer: B
Rationale: Specificity (B) is true negatives / (true negatives + false positives), ruling out non-diseased (e.g., 95% specificity = 95% healthy identified). A is sensitivity, C is NPV, D is an error.
Question 5 of 5
What does a likelihood ratio of less than 1 indicate?
Correct Answer: B
Rationale: LR < 1 (B) means a result favors non-disease (e.g., LR- = (1-sensitivity) / specificity). A, C, and D misinterpret.