Research and Evidence-Based Practice Flashcards

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

Answer: Level I — the highest level of evidence

Systematic reviews with meta-analyses represent Level I evidence, the highest quality in evidence-based practice hierarchies, because they synthesize data from multiple high-quality studies.

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

Answer: To eliminate selection bias and ensure group comparability

Randomization distributes known and unknown confounders equally between groups, reducing selection bias and ensuring the groups are comparable at baseline.

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

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

A p-value of 0.03 means there is a 3% probability of obtaining the observed results (or more extreme) if the null hypothesis were true, indicating statistical significance at the 0.05 level.

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

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

A 95% confidence interval means that if the study were repeated 100 times, approximately 95 of the resulting intervals would contain the true population parameter.

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

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

Sensitivity is the ability of a test to correctly identify true positives — in this case, patients who actually have malnutrition.

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

Answer: Randomized controlled trial

RCTs are the gold standard for establishing causality because randomization controls for confounding variables, allowing true cause-and-effect relationships to be determined.

Publication bias in nutrition research MOST often refers to:

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

Publication bias occurs when studies with positive or statistically significant results are more likely to be published than those with null or negative results, skewing the available evidence base.