Superfoods Research & Evidence-Based Practice 4

Question 1

The GRADE system used to evaluate superfood research evidence ranks 'RCT evidence' as high quality by default, but can downgrade it for which reason?

Accepted Answer

Risk of bias, inconsistency, indirectness, imprecision, or publication bias

Answer

GRADE (Grading of Recommendations Assessment, Development and Evaluation) downgrades RCT evidence based on methodological flaws, inconsistent results, surrogate endpoints, small samples, or selective reporting.

Question 2

A study reports that daily matcha tea consumption improved working memory in a 12-week trial. To evaluate generalizability, the most important question to ask is:

Accepted Answer

What was the study population, and how does it resemble target consumers?

Answer

Generalizability (external validity) depends on whether the study sample (age, health status, baseline diet) resembles the population to whom findings will be applied.

Question 3

Which statistical measure best indicates the practical significance (not just statistical significance) of a superfood intervention?

Accepted Answer

Effect size (e.g., Cohen's d or Hedges' g)

Answer

Effect size quantifies the magnitude of a difference or relationship, whereas a p-value only indicates whether an effect is unlikely due to chance regardless of its real-world importance.

Question 4

Polyphenol research frequently uses 'urinary metabolite excretion' as an outcome. What does this measurement assess?

Accepted Answer

The amount of polyphenols absorbed and metabolized by the body

Answer

Urinary excretion of polyphenol metabolites (e.g., hippuric acid, quercetin conjugates) reflects systemic absorption and metabolism, serving as a biomarker of actual exposure.

Question 5

A systematic review on spirulina finds only 6 eligible RCTs, all with fewer than 50 participants. The review's primary limitation is:

Accepted Answer

Insufficient statistical power to detect modest but real effects

Answer

Small trials are underpowered, meaning they may fail to detect true effects or produce unstable estimates, limiting the conclusions a systematic review can draw.

Superfoods Practice Test

Superfoods Practice Test

Superfoods Research & Evidence-Based Practice 4