Estimating and Assessing Nutritional Status and Intake Flashcards
1
Q
Methods of estimating usual dietary intake
A
- direct observation
- food records or diaries
- 24hr recalls
- FFQ
2
Q
Two Types of self-report instruments
A
short term ⇒ 24hr recalls, food records, diaries
long term ⇒ FFQ
- often used in large cohort or case-control studies to examine diet-health relationships
3
Q
Food Diaries / Records
Variations in Approach
A
- weighted record ⇒ quantitative
- estimated food diary/record ⇒ semiquantitative
- trained/untrained respondents
- detailed review or not
- highly standardized coding rules or not
- development of electronic methods
4
Q
Strengths of Food Records
A
- intake is quantified, detailed
- can include weekends
- could be accurate with detail and training
- data is rich in details - nutrients, cooking practices, frequency of meals and eating
5
Q
Limitations of Food Records
A
- recording influences diet (reactive tool)
- requires literacy
- high burden
- multiple days required for usual intake
- sample selection bias
- completion worse over time
- underreporting is typical
6
Q
24 Hour Recall
A
- amounts and foods consumed in 24 hour period prior to interview
7
Q
24 Hour Recall
Variations in Approach
A
- training of interviewer
- standardized probing questions
- computer vs paper administration
- in person or telephone
- portion size or measurement aids
- nutrient database used
8
Q
Strengths of 24 hour recalls
A
- low respondent burden and high compliance
- illiterate appropriate
- standardized protocol can be used
- unlikely to interfere with dietary behaviour
- large numbers of subjects
- possible to get details
9
Q
Limitations of 24 hour recalls
A
- memory
- portion size estimation
- multiple days required for usual intake - recall is just a snapshot
- costly / highly trained
- underreporting typical
10
Q
FFQ
variations in approach
A
- number of foods, clarity of questions
- portion size questions - pictures vs text description
- time frame
- development of food list - database
- type of administration
- supplement intake
- population of interest
- food preparation
11
Q
FFQ Strengths
A
- large number of people
- estimates usual intake
- does not affect eating behaviour
- low cost
12
Q
FFQ Limitations
A
- lacks detail ⇒ finite food list, details lost
- requires literacy
- affected by recent diet
- severe measurement error
- designed for different reasons
- different populations respond differently
- problems with food in composition
13
Q
Assessing FFQ
A
What was the original purpose?
Who was the target population? Are they suitable for other locations or populations?
When was it developed? Are the foods and sizes still relevant?
Has previous validation been carried out?
14
Q
Some important items to note when reading literature
A
- what database was used
- are valid estimations possible?
- is the correct level of precision reported?
15
Q
Assessing Nutritional Status
A
- intake and expenditure
- anthropometric
- clinical and physical findings
- biochemical data and medical tests
- behavioural and psychological contact
