Table 4 Intervention description summary

1. Incentives and rewards for follow-up clinic attendance

Ideally, participants could choose which financial reward (e.g. monetary, charitable donation/prefer not to receive) they would like to receive within the trial after completing all activities. Receipt of the financial rewards will be dependent on performing the activity, i.e. attending the clinic, and will be received at the final visit based on their overall attendance. Participants should be told during the recruitment discussion about the financial reward and the total amount that they would receive after attending all clinics. Participants should also be told that if they miss some visits, then that amount will be deducted from the total amount. In short, all participants who consented take part would have the opportunity to receive the reward but only those who attend the clinic would get the reward. The total financial reward should be explored with patient partners and should be reflective of the input required.

2. Goal setting for improving questionnaire return

During the informed consent consultation, provide an example of the questionnaire(s) and offer the potential participant an opportunity to work through. This will provide realistic expectations about what sort of questions will be presented and may help them to keep a record of these from the beginning (e.g. How much bodily pain have you had during the past 4 weeks?). Ask the participant to consider how many of the questionnaires they will commit to returning. Throughout the trial, participants will be reminded of the ‘goals’ agreed or set to encourage completion of all questionnaires, e.g. When sending the questionnaire, remind participants that during the consent discussion they agreed to complete trial follow-up.

3. Self-monitoring to improve questionnaire return and/or clinic attendance

If the questionnaires are paper based, provide a ‘loyalty’ card (indicating date when questionnaires are to be returned or clinic attendance). The card should be small enough to bring to visits without inconvenience. On the reverse of the card, mention the purpose of the trial and give details/photo of the point of contact. If electronic then provide electronic tracker or outlook planner and reminder. Given that the timing of questionnaires/clinics will likely depend on the date of randomisation, the card/planner will be delivered post-randomisation with key follow-up dates generated accordingly. Participants will receive a sticker (by post or a virtual sticker if by email) to put on the card/planner after the trial office has received each questionnaire, or after a visit has been attended.

4. Motivational information to improve questionnaire return and clinic attendance

Provide motivational information framed as positive reinforcement during the initial recruitment consultation, in the patient information leaflet (and supporting conversation) and throughout the trial during any patient contact or key trial touch points. The contents of the intervention should be tailored based on the trial, its participants and purposes. Remind participants about the focus and purpose of the trial and its possible impacts on future practice/guidelines (i.e., the end goal/bigger picture) and how their contribution is making a difference. You may want to identify the key potential benefits of being a research participant, such as tackling health issues/helping future generation/family members if they need a treatment for the same health condition in the future and that the more people who complete a task, the quicker the trial could help others. Keep thanking people for their contribution, for example, after every returned questionnaire or visit. State how others are doing in that trial for social comparison e.g.’ About 70% of people have come for this clinic appointment. We need everyone to come along for their visit to make sure that the results of the trial are as scientifically strong as they possibly can be.’ If the participant missed an activity, still encourage them saying they are still in the trial and that their continued contribution is still important and valued.