Table 4 Complexity principles underpinning group clinic delivery, including examples from the study and supporting quotes

Acknowledging uncertainty and unpredictability (e.g. through discovery, learning, and adaptation for multiple plausible futures)

A. Clinicians moved away from a formal, structured mode of delivery introduced at the beginning (e.g. set groups, formal letters) to embrace uncertainty and unpredictability through a ‘trial and error’ approach

B. Attendance in group clinics was unpredictable; facilitators initially found this unnerving but eventually acknowledged it as the norm and prepared for all eventualities

Q1: […] initially we started off with the groups, and we said we will stick to the same group, because we wanted to see how the groups evolved. And within one to two sessions I knew it was not going to work (Interview 1 Diabetes Specialist Nurse)

Q2: [...] people from first group couldn’t make that particular session, they wanted to join the second or third [group] and then keeping the register going and keeping a tab on who [attended] and when that was quite messy. (Interview 2 Diabetes Specialist Nurse)

Recognising self-organisation (e.g. local patterns of organising and implementation)

C. Established clinical and administrative patterns of organising for individual appointments in each setting hindered group clinic set-up and delivery (e.g. appointment systems, clinic times)—self-organisation was needed to overcome standard operational systems and to co-ordinate between clinicians

D. Group consultations were largely driven by participant input therefore relied heavily on patient self-organisation during clinics as well

Q3: […] just the booking process has created such a problem and how we created the list [for group clinics] because there’s just no infrastructure within the Trust to do group clinics. (Interview 18 Diabetes consultant)

Q4: […] it was the third session that I did that worked really well where we had the girls and they split up into separate groups and they planned their meals so they spoke about what they, within themselves, currently eat and then came up with ways that they can make it a bit better (Interview 3 Dietician)

Facilitating interdependencies (e.g. supporting effective and fostering new interdependencies)

E. Group sessions had to link with and feed into other care processes, such as one-to-one consultations and group education, and these interdependencies were often difficult to manage

F. To customise group clinics, diabetes specialist nurses required in-depth understanding of young people’s needs, acquired through their own experience and through discussions with other clinicians delivering one-to-one care

Q5: […] when they’re attending my appointment I found that in that group session nobody had looked at their Libre readings and actually highlighted the problems, talked about what changes they needed to make to their insulin on the pump. (Interview 18 Diabetes Consultant)

Q6: you really need to understand what are their interests, what are their troubles, to actually win their confidence […] in the beginning I spent a lot of time going through learning about each one of them, their history. (Interview 20, Diabetes Specialist Nurse)

Encouraging and accommodating sense-making (e.g. exchanging viewpoints and enabling ongoing, collective reflection)

G. A number of sense-making opportunities were needed to articulate and exchange viewpoints on what this model of care could best contribute

H. As a novel concept, group clinics became subject to much negotiation, including on the balance between clinical and educational content

Q7: When they know that other people are also going through the same problems [in group clinics], then it starts making them feel less guilty. And then that in turn will facilitate how they have the [one-to-one] conversation with their clinicians. (Interview 25 Diabetes consultant)

Q8: […] in the group clinic if there was eight people there and the nurses had to adjust the insulin for each person […] either everybody around would have found the readings interesting could have learned from that experience or they would have got completely bored. (Interview 18 Diabetes Consultant)

Developing adaptive capability (e.g. tinkering effectively with processes and making judgements)

I. Given group clinic delivery was not a standardised process, staff had to work creatively and flexibly to bring together young people, draw on existing expertise (clinical or other) within and outside the clinic, and sustain value for those involved (patients and clinicians alike)

Q9: if [speakers] are doing a presentation, I would ask them to send the presentation to me and I will look through it and make sure it's something that would benefit the participants […] you don't want to get them sort of bored by anything, you want to keep them sort of alive and asking questions. (Interview 26 Diabetes Specialist Nurse)

Attending to human relationships (e.g. working together to solve emergent problems)

J. Relationships were at the core of this new care model, both between clinicians to co-ordinate care for young people, between clinicians and patients, but also between patients as they were caring for each other in groups. This needed careful consideration of boundaries and interaction dynamics and required attention and time commitment

Q10: […] relationships take time to build, specially trusting relationships. […] And it’s not just me building relationships with the young adults, it’s me building relationships with the clinicians. (Interview 1 Diabetes Specialist Nurse)

Q11: […] it has been a quite rewarding and challenging experience for me, as well. So, every time I say something, I'm questioning myself again internally. So, is that too much for them? Is that too little for them? Or is it reaching everyone? (Interview 25 Diabetes Consultant)

Harnessing conflict productively (e.g. viewing conflicting perspectives as raw ingredients for multifaceted solutions)

K. Micro-conflicts emerged both among clinicians on how best to deliver group clinics and between young people on how best to self-care

Q12: […] in some of the sessions there’s been a bit of a conflict, and conflict management can be quite tricky. And I certainly know that the nurse was quite upset about it after that and so that needs a little bit of help. (Interview 18 Diabetes consultant)