Q: Which equation represents the calculation of absolute risk difference between two groups in a nutrition study?

$$\text{Absolute Risk Difference} = \text{Risk}_{\text{exposed}} - \text{Risk}_{\text{unexposed}}$$

Question 1

Which of the following best describes a 'spurious correlation' as illustrated by the link between cabbage consumption and innie bellybuttons?

Accepted Answer

A correlation that is statistically significant but likely due to random chance or confounding variables.

Question 2

Why are Food Frequency Questionnaires (FFQs) prone to error in nutrition studies?

Accepted Answer

They require participants to recall and estimate their food intake over long periods, which is difficult and often inaccurate.

Question 3

A study finds a statistically significant association between egg roll consumption and dog ownership. What is the most likely explanation for this finding?

Accepted Answer

The association is likely spurious, resulting from random chance in a large dataset.

Question 4

Which equation represents the calculation of absolute risk difference between two groups in a nutrition study?

Accepted Answer

$$	ext{Absolute Risk Difference} = 	ext{Risk}_{	ext{exposed}} - 	ext{Risk}_{	ext{unexposed}}$$

Question 5

If a food diary records 1,500 calories per day and an FFQ estimates 2,800 calories per day for the same individual, what is the difference in reported intake?

Accepted Answer

$$2,800 - 1,500 = 1,300$$ calories

Question 6

Which of the following is a major limitation of observational nutrition studies using memory-based dietary assessments?

Accepted Answer

They cannot reliably establish causality between diet and health outcomes.

Question 7

A nutrition study reports a relative risk of 3 for cancer in bacon eaters compared to non-bacon eaters. If the absolute risk is 0.01% for bacon eaters and 0.03% for non-bacon eaters, what does this imply?

Accepted Answer

The relative risk exaggerates the difference, while the absolute risk shows the actual impact is very small.

Question 8

What is 'p-hacking' in the context of nutrition research?

Accepted Answer

Manipulating data or statistical analyses to find significant results among many possible variable combinations.

Question 9

Which of the following best explains why FFQs often produce unreliable calorie estimates?

Accepted Answer

Participants struggle to accurately recall portion sizes and frequency of food consumption over long periods.

Question 10

A validation study compares FFQ results to 24-hour food recalls. What is a major criticism of this approach?

Accepted Answer

Both methods rely on subjective self-reporting, leading to circular validation.

Question 11

If a study runs 27,716 regressions with a p-value threshold of 0.05, how many false positives should be expected due to random chance?

Accepted Answer

$$27,716 	imes 0.05 = 1,385.8$$ false positives

Question 12

Which of the following is a plausible reason why food diaries may not accurately reflect usual eating patterns?

Accepted Answer

Participants may alter their eating behavior because they know they are being observed.

Question 13

Why is it problematic to use memory-based dietary assessments to set health care policies?

Accepted Answer

They are often inaccurate and may lead to misguided recommendations.

Question 14

Which formula would you use to estimate the number of days required to accurately measure average calorie intake for men, based on the study cited?

Accepted Answer

$$	ext{Days Required} = 27$$

Question 15

What is a key takeaway about the adaptability of human diets from the article?

Accepted Answer

Human bodies can thrive on a wide variety of diets, including those with few or many vegetables.

Question 16

Which of the following is an example of a biologically improbable finding in nutrition studies?

Accepted Answer

Eating three servings of nuts per week reduces mortality risk by nearly 40%.

Question 17

Why do headlines often report relative risk instead of absolute risk in nutrition studies?

Accepted Answer

Relative risk appears more dramatic and can exaggerate the perceived importance of findings.

Question 18

What is the main reason that nutrition studies frequently produce conflicting results about foods like coffee or butter?

Accepted Answer

Observational studies are limited by imprecise measurement tools and confounding variables.

Question 19

Which of the following best summarizes the current state of nutrition research methodology?

Accepted Answer

Current methods are limited and may require a major shift to improve accuracy.

Critical Evaluation of Nutrition Research: Methods, Challenges, and Interpretation

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