HSRT Evaluating Scientific Evidence 3

Question 1

A systematic review includes only studies published in English. This restriction introduces which type of bias?

Accepted Answer

Language bias

Answer

Attrition bias

Answer

Detection bias

Answer

Allocation bias

Question 2

A cohort study follows 5,000 smokers and 5,000 non-smokers for 20 years to compare lung cancer incidence. This design is best classified as:

Accepted Answer

Prospective cohort

Answer

Retrospective case-control

Answer

Cross-sectional

Answer

Ecological study

Question 3

Researchers report a confidence interval of 95% CI [0.85–1.15] for a risk ratio. What does this interval suggest?

Accepted Answer

The data are consistent with no meaningful difference between groups

Answer

The treatment doubles the risk of the outcome

Answer

The result is statistically significant at the 0.05 level

Answer

The true risk ratio will always fall between 0.85 and 1.15

Question 4

In evidence-based practice, which source of evidence should take precedence when making a clinical decision?

Accepted Answer

Current best research evidence integrated with clinical expertise and patient values

Answer

Anecdotal reports from experienced clinicians

Answer

The most recent guideline regardless of its supporting evidence

Answer

Studies funded by government agencies over industry-funded research

Question 5

A drug company funds a trial comparing its new medication to a competitor's. The trial shows superiority. Which concern most threatens the validity of this conclusion?

Accepted Answer

Industry funding may introduce reporting or design bias favoring the sponsor

Answer

The trial was randomized

Answer

The competitor drug is not commonly prescribed

Answer

The sample size exceeded 1,000 participants

Question 6

A researcher performs 20 separate hypothesis tests on one dataset and finds 1 significant result (p < 0.05). The most appropriate interpretation is:

Accepted Answer

One significant result is expected by chance alone when conducting 20 tests

Answer

The significant finding is a genuine discovery

Answer

The result should be replicated with the same dataset

Answer

A p-value below 0.05 is always conclusive regardless of the number of tests

Question 7

A health study uses self-reported dietary data collected via questionnaires administered years after the study period. This introduces which type of bias?

Accepted Answer

Recall bias

Answer

Selection bias

Answer

Observer bias

Answer

Allocation bias