Table 4.

Experience of the CAT^a-App: qualitative themes.

User experience, themes, and subthemes			Evidence
Therapists' experience
	Incorporating the app into clinical practice
		Promise of the app	“Some clients write a lot, others forget the paper or leave papers at school or home, especially younger clients.” (ID1)
		Using the app	“I introduced the app in the first session and then we would wait until session 5 before using it because it takes time to define the target problem procedures. I just cut and pasted from the letter straight into the app.” (ID3)
		Take up by patients	“All the clients were digitally literate. There was no hand holding and I told them to get back to me if they had any issues.” (ID3)
	Perceived threats and benefits
		Non-equivalence	“I didn’t want the app taking any decisions from therapists. I don’t want to be a virtual therapist.” (ID2)
		Anxiety regarding the app	“It felt like extra work [...] I was worried in case I uploaded the wrong information to the wrong account.” (ID2)
		Supporting self-reflection	“The app allows the client to become more of an observer of their behaviors than does the paper version.” (ID1)
		Anxiety regarding data protection	“We need to know exactly where the client’s data is stored and what happens to that data once the client is discharged, for example.” (ID2)
Patients' experience
	Data protection and storage
		Trust	“I trusted the therapist and the app” (ID4) “I’m more bothered about bank details than emotional stuff” (ID9)
		Normality of data sharing	“What’s the worst that could happen?” (ID4) “I’m happy with the Ts & Cs. I don’t really read them anyway” (ID5)
		Server felt safe	“It’s better than paper, I can’t lose it” (data) (ID6) “It’s good the data isn’t on my phone. It means I can only work online but at least nothing is saved on my phone” (ID 5)
	Motivation and engagement
		Initial excitement	“I like the idea, I set it all up straight away” (ID4) “Initially I thought it was a great idea, better than using paper” (ID 7) “I was excited to try, I’ll give these things a go” (ID 8)
		Reminders	“I liked it but I’m not driven to use it, I needed more discipline. Maybe nudges as well as reminders would help” (ID4) “You can set reminders to use it but it would be good to have thought provoking messages as well, relating to CAT” (8)
		Habit forming	“I didn’t have access for 3 weeks when I was abroad. I got used to using paper and just stuck with that” (ID7) “It made me more conscious of my targets in the day. Knowing I could just not something down or reflect. I found it useful” (ID5)
	Restrictions and flexibility
		Online/offline access	“It’s good that data is stored on a server but that means I can only use it if I’m online. It needs a save and sync option” (ID5)
		Convenience	“It was good to make notes as and when I needed to” (ID8) “It was a great place to deposit feeling and later revisit them in the evening to make sense of them. You forget sometimes in the middle of the day and then you don’t feel as extreme later. It was good to note things quickly to analyze” (ID4) “I liked how my therapist could access things. It was on way but she could look at things with me and help make sense of things. Everything was in one place which was convenient” (ID5)
		Free writing	“I preferred paper once I got going. I liked to see my maps and patterns as I wrote. I referred back to them. I found the journaling therapeutic, physically writing worked for me” (ID6) “I would have liked more free text journaling. I found that really helpful on paper” (ID8)
		Restrictive	“I found the targets were too simple for my case. My issues were more complex and the app couldn’t be tailored as much as I needed” (ID8)
		Ambiguity	“When it came to recognitions I was confused – not seen – fully recognized. What if it didn’t apply that day?” (ID7) “The scales need numbering or more detail. What is the middle of a scale? It’s too ambiguous” (ID5)
		Creative additions and personalization	“It would be good to be able to zoom in on areas of the map. Have it be more interactive with therapists notes/audio, reminding me of the focus and available coping or exits” (ID4) “I’d like the exits to link to a storage of best coping strategies. So they are just there right away for you to draw on” (ID4) “I would have liked to change the colors of the app to make them more welcoming” (ID2) “If you could create a character in the app, to guided you, engage with, that gets to know you, that would be good” (ID9)

^aCognitive analytic therapy.