Table 6.

Themes, TFA constructs, and supportive narratives from therapist interviews

	TFA constructs	Supporting excerpts
Training acceptability barriers	Opportunity costs	“In a busy NHS clinic, there's always pressure on patients and waiting times, two days out of a clinic is a big ask it did have a knock-on effect, and a potential impact on patient care” (01_002)
Training acceptability enablers	Affective attitude	“it was a really nice small, friendly, informal environment” (03_003)
	Perceived effectiveness	“The packaging that we got was excellent, there wasn't anything that was left out, I actually refer to training materials a lot in clinic, everything was really well done” (03_004)
	Self-efficacy	“I felt confident doing the MI practice because I’ve had training before” (03_003)
Intervention delivery acceptability barriers	Burden	“It definitely felt like there’s a lot of paperwork. Putting it all together in a sequence with all the paperwork in front of you … that felt like there was quite a lot to do for one appointment” (03_003)
Intervention delivery acceptability enablers	Intervention coherence	“The follow-up sessions were good to check if we’d changed something in the second consultation and I just wanted to make sure that they were managing the alterations that we’d agreed and to make sure that they were happy in what they were doing” (03_001)
	Perceived effectiveness	“The ones that were motivated and committed to it and did it, were thrilled at how quickly they started to pick up the exercises. They could see the changes in themselves, so, it definitely is effective” (02_001)