Nutrition knowledge questionnaire
Nutrition knowledge was assessed using the validated General
Nutrition Knowledge Questionnaire which included four domains
(1) advice from health experts (11 items, e.g. which fat do experts say
is most important to cut down on?), (2) food groups and food sources
(71 items, e.g. are these foods high in salt?), (3) food choice (12 items,
e.g. what is the best choice for a low-fat, high fibre snack?) and
(4) diet–disease relationships (22 items, e.g. what major health problems
are related to a low fibre intake?) (Parmenter andWardle, 1999).
Nine questions were modified to include recent evidence in nutrition
knowledge (e.g. what health problems are related to excess sugar?).
Food items were altered to increase participants' understanding (e.g.
orange juice instead of orange squash).
Participants were asked to complete all questions. Each correct answer
scored 1. Incorrect and missing values scored 0. Subscale scores
were calculated for each domain. The sum of the four sections was calculated
to give a maximum potential score of 116. The overall nutrition
knowledge score was divided into quintiles. Participants in quintile 5
scored highest for nutrition knowledge.