Data analysis and integration
Qualitative data were examined using framework analysis supported by NVivo (version 12). Two researchers conducted interviews and checked transcripts. Through familiarisation with the transcripts, examination of the interview schedules, and the three MRC framework domains, a set of a priori categories were developed to form an initial framework (Framework of categories and codes
Transcripts were coded independently (by the same two authors). An ‘other’ category was included in the framework to include relevant data that did not readily fit into the pre-existing categories. Although categories applied to each of the groups interviewed (nurse, patient, and practice manager/GP), the codes were specific to each group as outlined in Quantitative measures were presented at baseline (ISI and sleep efficiency) and at the nurse follow-up appointments (sleep efficiency) to show changes during treatment. Relationships between qualitative findings, nurse records, and quantitative measures were explored and presented using a joint display (see Supplementary Table S1) allowing for direct comparison of the patient perceptions of SRT with changes to their measured sleep efficiency.