Summary of findings 2. Hypnotherapy compared with control for children and adolescents with recurrent abdominal pain.

Hypnotherapy compared with control for children and adolescents with recurrent abdominal pain
Patient or population: children and adolescents with recurrent abdominal pain Settings: mixed Intervention: hypnotherapy Comparison: usual care or wait‐list control
Outcomes	Probable outcome with control or usual care	Probable outcome with hypnotherapy	OR (95% CI)	Number of participants (studies)	Quality of the evidence (GRADE)	Comments
Treatment success: postintervention	136 per 1000	525 per 1000	Pooled OR 6.78 (2.41 to 19.07)	146 (4)	⊕⊕⊝⊝ 1 Low	2 studies defined treatment success or remission as > 80% decrease in pain intensity. 1 study used the definition of "4 or less days of pain per month and no missed activities" and 1 study as "> 50% reduction in API" (Walker 1997).
Pain intensity: postintervention Lower score equals less pain.	The pain intensity score in the hypnotherapy groups was, on average, 1.01 SDs lower (95% CI ‐1.41 to ‐0.61) than in the usual care or wait‐list control groups.		—	146 (4)	⊕⊕⊝⊝ 1 Low	As a rule of thumb, 0.2 SD represents a small difference, 0.5 SD a moderate difference, and 0.8 SD a large difference. 1.3 represents a large effect difference. Pain intensity measured by 2 different scales (the FACES Pain Scale and the API (Bieri 1990; Walker 1997)).
Pain frequency: postintervention Lower score equals less pain.	The pain frequency score in the hypnotherapy groups was, on average, 1.28 SDs lower (95% CI ‐1.84 to ‐0.72) than in the usual care or wait‐list control groups.		—	146 (4)	⊕⊕⊝⊝ 1 Low	As a rule of thumb, 0.2 SD represents a small difference, 0.5 SD a moderate difference, and 0.8 SD a large difference. 1.50 SD represents a large effect difference. Pain frequency measured by different scales (bespoke pain diary recording the number of days; daily scale ranging from 0 to 3, summed over 7 days; and API, range 1 to 8 (Walker 1997)).
API: Abdominal Pain Index; CI: confidence interval; OR: odds ratio; SD: standard deviation
GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate.

¹Downgraded two levels: a high risk of bias across the studies in study design and outcome assessment (unblinded allocation and assessment, wait‐list control) and a low number of participants included in the analysis or low number of events.