Chapter 3: Measuring Diet Flashcards

Flashcards covering concepts, methodologies, strengths, and limitations of dietary measurement techniques based on Nutritional Assessment, 7e (Chapter 3).

What are the four main reasons for measuring diet according to Box 3.1?

1. Assessing and monitoring food and nutrient intake, 2. Formulating and evaluating government health and agricultural policy, 3. Conducting epidemiologic research, 4. Commercial purposes.

What key finding was demonstrated in the 1975 ecological study by Armstrong and Doll?

An association between per capita meat consumption and the annual incidence of colon cancer per 100,000 women in various countries.

What is a major limitation of ecological studies in dietary assessment research?

Although useful at generating hypotheses, ecological studies are not capable of testing hypotheses.

What relationship between age and hypertension was shown by NHANES data between 2011 and 2014?

The prevalence of hypertension increases as Americans age.

What are the primary strengths of the 24-hour recall method?

It requires less than 20 minutes to administer, is inexpensive, is easy to administer, provides detailed information on food types, has low respondent burden, allows probability sampling, estimates group nutrient intake, does not alter usual diet, and is useful in clinical settings.

What are the main limitations of relying on a single 24-hour recall?

It is seldom representative of a person's usual intake, relies on memory, is subject to underreporting or overreporting, can underestimate energy due to omitted items (dressings, beverages), and data entry can be labor intensive.

How do estimated food records and weighed food records differ in measurement technique?

Estimated food records use household measures or estimates quantified by researchers by volume and weight, whereas weighed food records use scales or computerized techniques supplied by researchers to weigh foods and leftovers.

Up to how many days is a food record considered reasonably valid?

Up to five days.

What are the three main formats of Food Frequency Questionnaires (FFQs)?

1. The simple, or nonquantitative format, 2. The semiquantitative format, 3. The quantitative format.

What is the purpose of the National Cancer Institute's Quick Food Scan dietary screener?

To estimate an individual's usual intake of percent of energy from fat.

Why is the Food Frequency Questionnaire (FFQ) considered by some to be the method of choice for research on diet-disease relationships?

It can be self-administered, is machine readable, places modest demand on respondents, is relatively inexpensive for large sample sizes, and may be more representative of usual intake than a few days of diet records.

What are the strengths of the diet history method?

It assesses usual nutrient intake, can detect seasonal changes, provides data on all nutrients, and can correlate well with biochemical measures.

What is the main strength and a major limitation of the duplicate food collection method?

The strength is providing more accurate measurements of actual nutrient intake than calculations based on food composition tables; limitations include high expense and effort to collect samples, as well as potential underestimation of usual intake.

What is a key limitation of the food account method?

It does not account for food losses and is not appropriate for measuring individual food consumption.

What is the purpose and primary limitation of a Food Balance Sheet?

It gives a total view of a country's food supplies and indicates trends for international planning, but it only represents food available for consumption (not actual consumption) and does not account for wasted food.

How do the costs of telephone interviews compare to personal interviews in dietary assessment?

Telephone interviews cost one-quarter to one-half the cost of a comparable personal interview.

What is the function of a fiducial marker in digital imaging of meals?

It assists researchers in accurately estimating portion sizes of food items in digital photographs.

What are the primary limitations of digital imaging methods for dietary assessment?

Large initial expense, need for periodic revalidations, inability to visually distinguish similar foods or document preparation methods, and potential technical equipment problems.

Which specific population groups may require adaptations in dietary measurement according to Box 3.12?

Young persons, persons with recall problems, vision- or hearing-impaired persons, persons who cannot read well, and the obese.

How is relative (or criterion) validity defined in dietary assessment?

The comparison of a new instrument with another instrument (a so-called gold standard) that has a greater degree of demonstrated (face) validity.

How is reproducibility (or reliability) defined in dietary assessment?

The ability of a method to produce the same estimate on two or more occasions, assuming that nothing has changed in the interim.

What features in the USDA Food Model Booklet assist respondents in estimating food portion sizes?

A life-size dinner plate image with four different-sized amorphous mounds (with a knife across the top as a size reference) and a superimposed grid to estimate the length and width of square or rectangular foods.