A Cochrane review included 11 studies with 18 different control interventions. The results were conflicting for the effectiveness of hypnotherapy compared to no treatment, or to advice, or psychological treatment. There was no evidence of an effect of hypnotherapy compared to rapid smoking or psychological treatment. Direct comparisons of hypnotherapy with cessation treatments considered to be effective had confidence intervals that were too wide to infer equivalence.
Comment: The quality of evidence is downgraded by inconsistency (heterogeneity in interventions and outcomes) and limitations in study quality.