Table 2.

Framework analysis.

Themes and topic summaries		Example quotations
Independent use and personal fit
	Having agency, taking responsibility, self-discipline, and self-growth	“The advantages are the independence and the self-control and the mindfulness and those skills in themselves, the self-discipline as well, they can [be used] in their own treatments and their own self-discovery journeys.” [Participant 10]
	Matches lifestyle and preferences	“So, like an advantage of this is especially for people who are suffering anxiety and PTSD and don’t get out.” [Participant 5]
	Provides privacy, safety, and flexibility	“When you’re on your own, you sort of have time to think and like go through the answers at your own pace and when it suits you.” [Participant 12]
	Ability, or otherwise, to complete without assistance: neurodiversity, language barrier, and technological proficiency	“I was able to do it myself but for other people, there’s a chance they might need assistance. It could be because they have like dyslexia or there is a language barrier.” [Participant 7]
Digital versus traditional approaches
	Advantages of apps over traditional therapies	“[T]here’s less need for human intervention because the app is friendly and fun.” [Participant 8]
	Disadvantages compared to traditional therapies: digital exclusion, dropout rate, lack of feedback, distractions, and potential dependence on the app	“You don’t get personalized feedback like you would with a person.” [Participant 1]
	Focused, structured, and specific intervention	“[Usually a] therapist can guide it, whereas I like the way that this was more structured and forced you to think through different scenarios. And I like that aspect of it.” [Participant 1]
User reactions and emotional impact
	Perceived as judgmental, patronizing, and invalidating	“There is nothing to validate you or to say your initial response actually had some value in it.” [Participant 1]
	Validating and normalizing	“It is validating. It’s almost as if the researchers have taken into account that we struggle with these thoughts, no matter how insignificant they seem.” [Participant 4]
	Elicited mixed feelings: confusion, excitement, fear and embarrassment, hope, sadness, or neutral	“I think I possibly felt more sad at the end of each session.” [Participant 9] “I would look forward to it, it was interesting.” [Participant 2] “It’s not good, nor bad.” [Participant 7]
	Evocative and triggering of actual experiences	“They’re very good at conveying the paranoid thoughts, they were very evocative and brought up quite a lot of feelings when reading them.” [Participant 9]
	Perceived as restrictive	“One negative thing was that it doesn’t let you say no, I don’t agree with that.” [Participant 5]
Impact on thinking, awareness, and well-being
	Helpful impact on daily life and thinking patterns, sense of achievement, and general positive feelings	“I found it really helpful...it has been giving me some clues like some other way of thinking other than like me, always overthinking what other people’s intentions are.” [Participant 4]
	Offers new perspectives	“I found one of the big values of the app is identifying other options and other ways of looking at things.” [Participant 1]
	Self-reflection, awareness, and understanding of paranoia and its presence in the user’s life	“It has made me realize how insidious paranoia and anxiety are in my everyday life via the scenarios, for which I was always instinctively drawn to the negative assumptions, and so many of which I regularly worry about.” [Participant 9]
Design, engagement, and usability
	Design and look of the app	“I think the color scheme is very calming and soothing...I think it's quite good like, it’s not really intimidating or like causing people distress.” [Participant 4]
	Engagement with the app	“Intuitive, really well designed and written, and very engaging.” [Participant 9] “It was a bit like a reading comprehension for a 7-year-old.” [Participant 10]
	Suggestions for improvement: managing expectations, personalizing the experience, suggestions for design changes, and access to the app	—a
Intervention relevance and practical fit
	Acceptability and testing of scenarios	“So, about half I think were quite pretty easy to identify with and about half I had to work a bit harder.” [Participant 1] “I thought they’re all very relatable...there wasn’t a single one that I thought it seemed odd or shouldn’t be in there.” [Participant 8]
	Perceived difficulty of the intervention	“Yeah, I guess the more effort just like you’d have to think about it more to try and work out what that word is instead of like ‘Ohh well, clearly it has this like one word that fits in there.’” [Participant 11] “It was like there’s always a very obvious word that fits in...if it was more challenging, I’d probably focus more on the sentence.” [Participant 12] “I had to think about it more, and that’s not necessarily a bad thing...those were the scenarios which helped me the most.” [Participant 1]
	Session frequency and duration	“I would say it’s just about right, but it’s not a little ask. It took me, I would say just over half an hour...that’s still a fair commitment. Possibly for some people would need it to be a bit shorter.” [Participant 1] “I would like it to be on a continuous basis.” [Participant 4] “It was quite long as well. The sessions were longer than expected...Maybe if the session were half the length as well, then I wouldn’t have got bored so quick so easily.” [Participant 10]
	Views and suggestions related to implementation	“I’m severely disabled, that’s what’s unrelatable. Maybe the app is aimed at people who have less severe disabilities. And yet I did find it helpful.” [Participant 11]

^aSuggestions are presented in Multimedia Appendix 3.