Berding 2017.

Study characteristics
Methods	Study design: prospective RCT Study duration: 2011‐2015 Setting: IBD referral centres
Participants	State of disease at beginning of study per IG/CG: inactive or low disease activity Disease type per IG/CG: mean (SD) Crohn’s disease: IG 3.1 (1.9); CG 3.8 (2.4) 0.096 Ulcerative colitis: IG 2.9 (3.0) CG 4.1 (3.2) Inclusion criteria: patients aged 18 or over with an established diagnosis of IBD Exclusion: insufficient language skills, severe vision or hearing impairment, serious physical or psychological comorbidity. Attendance at an IBD education programme up to 6 months before the study. Age at beginning of study per IG/CG: Mean (SD) IG: 39.6 (13.2); CG 40.1 (12.3) Sex per IG/CG: IG: 33.7% of 86 = 29 men, 57 women CG: 28.4% of 95 = 27 men, 68 women Disease duration per IC/CG: mean (SD) years IG: 10.9 (10.8); CG: 9.6 (8.9) Number randomised per IG/CG: IG 105; CG 102 Number reaching end of study per IG/CG: IG 84; CG 95
Interventions	IG: a 2‐part patient education seminar involving tasks and discussions covering medical information and coping and self‐management skills lasting for 11.5 hours over two days. CG: treatment as usual (no education)
Outcomes	Duration of follow ‐up: 3 months Primary outcomes as defined by study authors: disease related worries and concerns measured using the Rating Form of the IBD Patient Concerns Questionnaire Secondary outcomes as defined by study authors: fear of progression, coping with anxiety, health competencies, HRQoL, symptoms of depression and anxiety, disease‐related knowledge and coping strategies
Notes	Funding source: German Federal Ministry of Education and Research, the German Pension Insurance, the National Association of Statutory Health Insurers and Association of Private Health Insurers. Funding number 01GX1001. Conflicts of interest: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated numbers used.
Allocation concealment (selection bias)	Unclear risk	Author states "To ensure allocation concealment, central block randomization (ratio 1: 1) was used", but this explanation does not ensure allocation concealment. Authors were contacted, no response was received.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Blinding not possible due to the nature of the intervention (patient education).
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No mention of blinding of outcome assessment. Authors were contacted, no response was received.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The intervention group lost 21/105 (attendance issues n =19, did not return questionnaires n = 2) and the wait list group lost 7/102 (did not return questionnaires n=7). In the end, there is no major imbalance, taking into account the nature of the comparison and the outcomes assessed.
Selective reporting (reporting bias)	Unclear risk	No protocol or trial registration. Outcomes presented in the methods section were clearly presented.
Other bias	Low risk	No baseline imbalances, however the baseline characteristics are only presented for the completers and not for all randomised patients who completed the baseline assessment. No other concerns.