Table 2.

Coding frame

Code and definition	Description	Example quotes from participants
1. Questioned the wording of the item	Participants did not understand and criticised specific words in the questions. This issue had appeared 21 times across ten items when participants expressed doubts about how the questions were worded. Most often this issue appeared in response to item 4 of the ORTO-15. Individuals openly admitted to not understanding some of the words used in ORTO-15	P16 in response to item 4: When I feel overweight and unhappy with my body image, this motivated me to eat healthier. It particularly works when I start to see a physical change. The question is a little confusing as some people have a different interpretation of a ‘health status’ P49 in response to item 8: Transgressing is the wrong word, the implication that my food rules are law is rather extreme. Also, not everybody understands the meaning of transgressing P18 in response to item 8: I find this question ambiguous, it’s not a word I associate with eating. I guess it means going beyond the eating limit?…
2. Did not understand the meaning	When participants did not understand the meaning of the question, provided statements unrelated to the item, and questioned the sensibleness of the item. This problem came up 79 times across all the items when participants struggled to understand what the question was asking. This issue was especially pronounced across items 2 and 10	P29 in response to item 7: Don’t really understand the question P36 in response to item 2: I don’t understand what there is to be confused about! P37 in response to item 14: This question is slightly confusing to understand, but I do think that there is a lot of unhealthy food available, and sometimes this is dressed up as being good for you. However, I am not entirely sure what this question is asking P1 in response to item 5: Hard question…something that tastes good is not necessarily quality, depending on how you measure it.” and “all of this is more complicated than can be answered here… P26 in response to item 2: What do you mean by more money? More than I usually spend? Healthier than what?…
3. Agreed only to a part of the question	When participants’ answers indicate partial agreement or disagreement with the question often based on additional information, conditions, or situations. This issue appeared 46 times across the data. Most often it was observed in item 5. Participants expressed their agreement or disagreement with the question based on additional reasoning suggesting that they applied their own frame of reference influenced by alternatives created by the individuals to answer this question	P3 in response to item 12: I think that consuming healthy food can improve your appearance if it is eaten in the right portion sizes… P4 in response to item 12: Eating healthy has been proven to clear skin, but again it’s like a placebo, although it works, it doesn’t happen overnight P43 in response ot item 5: Sometimes when I’m cooking my own meal I don’t worry about what I’m putting in it, I just do what will make it taste better, but if I was out buying food that’s when I calorie-count
4. Qualitative response did not concord with quantitative response to questionnaire item	When there is a difference between the reasoning in participants’ comments and their response in the questionnaire. This issue has appeared 35 times across 13 items with the most comments clustering in item 3	P18 chose “never” as a quantitative response to item 3 while the qualitative comment indicates the opposite to be true: “When I am consciously eating healthy I always worry about my food choices. Especially when having a good social life, it includes a lot of bad food and drink choices which makes me worry about food” P41 also chose the quantitative response “never” while the qualitative comment indicated: “I'm always worried about what to eat due to my weight issues”
5. No problem	When participants did not encounter any difficulties answering the question