Table 1 Qualitative feedback questions on the intervention

1. How relevant and useful was the intervention was to your own experiences (if you have them) of symptoms of perfectionism, anxiety, depression or eating disorders? If you do not have these experiences, how useful do you think the intervention would be for other parents/carers of teenagers with eating disorders for the parents/carers perfectionism or symptoms?

2. Can you please tell me how useful the intervention was for helping your teen with perfectionism, and symptoms of eating disorders, anxiety and depression? Did you follow up each session and work through it with your child?

3. What did you like about the intervention?

4. What did you not like about the intervention?

5. Any suggestions for what you think is missing from the intervention, or what you would have liked?

6. What other areas do you think could be useful or relevant for the intervention to cover?

7. Do you have any other comments you think we should consider in what would appeal to you or others in an intervention for parents/carers to support their teenager in working through perfectionism?

8. Would you have preferred to have some guidance in using the intervention or work through it on your own as you did?

9. Would you recommend the intervention to other parents/carers?

10. Do you have any further comments you think are important for us to consider?