RDN Research and Evidence-Based Practice

Question 1

A systematic review with meta-analysis is considered which level of evidence in evidence-based dietetics practice?

Accepted Answer

Level I — the highest level of evidence

Answer

Level II evidence

Answer

Level III evidence

Answer

Level IV — the lowest level of evidence

Question 2

In a randomized controlled trial (RCT), what is the PRIMARY purpose of randomization?

Accepted Answer

To eliminate selection bias and ensure group comparability

Answer

To reduce study costs and duration

Answer

To increase the overall sample size

Answer

To blind participants to their treatment assignment

Question 3

A study reports a p-value of 0.03. This BEST indicates that:

Accepted Answer

There is a 3% probability the observed results occurred by chance alone if the null hypothesis is true

Answer

The results are clinically significant and meaningful

Answer

The null hypothesis is accepted

Answer

The effect size observed in the study is large

Question 4

A 95% confidence interval for a relative risk is reported as 1.2–3.4. This means:

Accepted Answer

We are 95% confident the true relative risk lies between 1.2 and 3.4

Answer

The true value falls outside this range 95% of the time

Answer

The result is not statistically significant because 1.0 is excluded

Answer

The study had a 5% measurement error rate

Question 5

A malnutrition screening tool has high sensitivity. This PRIMARILY means the tool:

Accepted Answer

Correctly identifies most people WITH malnutrition (high true positive rate)

Answer

Correctly identifies most people WITHOUT malnutrition (high true negative rate)

Answer

Has a very low false positive rate

Answer

Is also highly specific

Question 6

Which study design is BEST suited to establish a causal relationship between a dietary pattern and disease?

Accepted Answer

Randomized controlled trial

Answer

Cross-sectional study

Answer

Case-control study

Answer

Ecological study

Question 7

Publication bias in nutrition research MOST often refers to:

Accepted Answer

The tendency for journals to preferentially publish positive or statistically significant findings

Answer

Bias introduced when authors publish under pen names

Answer

Errors in the bibliographic references of published studies

Answer

Restricting publications to only high-impact-factor journals