Samenvatting HNE-32806
Lecture 1 – Evaluation studies
Aim of this lecture:
- Refresh knowledge on dietary assessment methods
- Importance of errors in dietary assessment
- Overview of the nature of evaluation studies
- Definitions of important concepts: validity, reproducibility, reliability
Refresh knowledge on dietary assessment methods
Dimensions in dietary assessment methods
Assessment method Dimension
Observation unit Individual, household, group
Mode of administration Double portion collection
Record (mail, with or without check, observation)
Interview (phone, face to face, computerised, video)
Time frame Past intake (usual, recent past), current intake
Measurements of amounts of foods Weighing, estimation with/without models, photos
Conversion into nutrients Nutrient database, direct chemical analysis
FFQ – food frequency questionnaire
- Principle:
o Frequency of habitual intake
- Application
o Easy
o In large studies
- Disadvantages
o Difficult to recall past intake
o No information on single foods
Food record
- Principle
o Record current intake
o Amount and time eaten
- Application:
o Experiments
o Small studies
o Awareness of intake (intervention)
- Disadvantages
o Change of intake (as a reaction to the record)
o Burdensome (weighing)
Lecture 1 – Evaluation studies
Aim of this lecture:
- Refresh knowledge on dietary assessment methods
- Importance of errors in dietary assessment
- Overview of the nature of evaluation studies
- Definitions of important concepts: validity, reproducibility, reliability
Refresh knowledge on dietary assessment methods
Dimensions in dietary assessment methods
Assessment method Dimension
Observation unit Individual, household, group
Mode of administration Double portion collection
Record (mail, with or without check, observation)
Interview (phone, face to face, computerised, video)
Time frame Past intake (usual, recent past), current intake
Measurements of amounts of foods Weighing, estimation with/without models, photos
Conversion into nutrients Nutrient database, direct chemical analysis
FFQ – food frequency questionnaire
- Principle:
o Frequency of habitual intake
- Application
o Easy
o In large studies
- Disadvantages
o Difficult to recall past intake
o No information on single foods
Food record
- Principle
o Record current intake
o Amount and time eaten
- Application:
o Experiments
o Small studies
o Awareness of intake (intervention)
- Disadvantages
o Change of intake (as a reaction to the record)
o Burdensome (weighing)
