In addition to the main study, a qualitative sub study will also be conducted. This nested study aims to assess the acceptability and adherence to the treatment interventions in the trial. This will facilitate evaluation of the interventions based on the experiences of healthcare practitioners and patients in delivering and receiving the intervention respectively; and will be used to inform the results of the main trial.
After receiving the intervention, a small number of participants (approx. 30 – 40) who consented at trial entry to being contacted about the interview study, will be invited to participate in semi structured interviews. Healthcare practitioners (approx. 10 -15), delivering the trial interventions will also be contacted and invited to participate.
A separate information sheet and consent form will be used for the qualitative interviews. Interviews will be held at a convenient time and location for each participant. Ideally interviews will be undertaken face-to-face, however, given the geographical spread of participants, it may be more practical to perform some interviews by telephone or online (e.g. Skype). Participants may choose to have the interview within their own home in which case the researcher must adhere to the Oxford University and/ or Trust lone worker policy. It is predicted from previous experience that each interview will last between 30-45 mins.
Purposive sampling will be carried out to achieve a sample which includes; participants who were randomised to the surgical or rehabilitation intervention and those in the rehabilitation arm who subsequently decide to have surgery.
All interviews will be audio recorded, transcribed verbatim and analysed with the assistance of Nvivo qualitative data analysis software (QSR International Ltd, Melbourne, Australia). Field notes and memos will be recorded using a digital notepad. Participants will be offered the opportunity to check their transcript, providing an opportunity for them to remove anything with which they do not feel comfortable.