Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
RCT	169 people; 90 (53%) with episodic cluster headache, 78 (47%) with chronic cluster headache In review	Adverse effects 31/89 (35%) with sumatriptan (100 mg three times a day) 19/79 (24%) with placebo	Significance not assessed