Collecting Dietary Data

Question 1

Diet history (overview)

Answer 1

Used in clinical interviews to identify usual intake of an individual
- recall yesterday’s intake
- description of ‘usual’ intake
- cross check of key food / food groups
Goal to identify food patterns across time.

Question 2

Diet history strengths

Answer 2

Better capacity to capture usual intake

Question 3

Diet history weaknesses

Answer 3

• time consuming
• requires skilled interviewer
• difficult for those with irregular and varied eating habits
• people forget and conceal info

Question 4

24 hour recall description

Answer 4

Subject recalls everything they consumed in the past 24 hours (midnight - midnight).
Commonly used in nutrition surveys to obtain food intakes for a population.
Uses “multi-pass approach” .
Recommended to collect data across multiple days

Question 5

24 hour recall strengths

Answer 5

• easy to collect data
• Reasonably accurate - easier to remember last 24 hours
• suitable for messing mean and distribution of intakes in groups

Question 6

24 hour recall weaknesses

Answer 6

• Single recall unlikely to capture usual intake
• Difficult to capture portions accurately
• People can forget or conceal info

Question 7

Food Frequency Questionnaire

Answer 7

• Structured questionnaire to obtain info on typical intake of population
• Asks how frequently ppl eat a range of listed foods in a defined time period
• may also ask for estimated quantity
• may be targeted to capture specific nutrients or food components or broadly asses dietary patterns

Question 8

Food frequency questionnaire strength

Answer 8

Potential to capture usual intake of a population

Question 9

Food frequency questionnaire weaknesses

Answer 9

• requires good understanding of “serves”
• poorly constructed list could miss key foods
• people can forget or conceal information

Question 10

Food record

Answer 10

• Subject records food as they are eaten (paper / app etc)
• useful for capturing actual intake
• can weigh foods or use household measures to estimate portions
• can combine with image capture
• need to consider number of days recorded

Question 11

Food record strengths

Answer 11

• less reliance on memory
• potentially more accurate quantification
• can capture usual intake if sufficient days are recorded

Question 12

Food record weaknesses

Answer 12

• Compliance (requires time and effort)
• unintentional or intentional changes to eating habits
• difficult for people with low literacy and numeracy
• errors of memory still possible

Question 13

How many days should be recorded in a food record?

Answer 13

3-7 days for macronutrients
Longer for micronutrients

Question 14

Direct observation

Answer 14

• Subjects observed eating (aged care homes, schools, food courts)
• May surreptitiously weigh food eaten
• can use ‘duplicate portion’ method

Question 15

Direct observation strength

Answer 15

Can capture intake very accurately

Question 16

Direct observation weaknesses

Answer 16

• labour intensive
• often limited to ‘artificially constructed’ situations

Question 17

Direct observation weaknesses

Answer 17

• labour intensive
• often limited to ‘artificially constructed solutions’