Data analysis
ATLAS.ti 7, a computer programme for qualitative data analysis, was used to support coding the interviews. Analysis of the anonymous transcripts started as soon as the first interviews had been transcribed and was an iterative process using an inductive approach to comparative content analysis [18,19]. Two researchers (AP, AVL) independently read all transcripts and applied codes to meaningful words or sentences. Codes were discussed, seeking agreement for their content. New codes arising from these discussions were applied to the transcripts. Codes were grouped into themes, and final themes were agreed upon with the supervisory committee (all authors). Themes were used to adapt the interview topic guide and to progressively focus and explore data in-depth. After analysis of 16 interviews with 12 different patients, no significant new codes emerged. Conduction and analysis of five additional interviews confirmed saturation.