1. Overview of interventions.

Study	Country	Surgical technique		Concurrent adenoidectomy (%)
		Tonsillectomy	Tonsillotomy
Dai 2014	China	Coblation	Coblation	Not stated
Li 2013	China	Coblation	Coblation	100
Zhou 2016	China	Not stated	Not stated	100
Chaidas 2013	Greece	Blunt dissection	Blunt dissection	100
Skoulakis 2007	Greece	Blunt dissection	Blunt dissection	100
Kordeluk 2016	Israel	Electrocautery	CO2 laser/microdebrider	100
Bitar 2016	Lebanon	Electrocautery	Microdebrider	Not stated
Borgstrom 2017	Sweden	Blunt dissection	Coblation	100
Densert 2001	Sweden	Blunt dissection	CO2 laser	(100 previously)
Ericsson 2009	Sweden	Blunt dissection	Radiofrequency	80
Hultcrantz 1999	Sweden	Blunt dissection	CO2 laser	15
Hultcrantz 2004	Sweden	Blunt dissection	Radiofrequency	49
Lundeborg 2009	Sweden	Blunt dissection	Radiofrequency	79 (10 previously)
Beriat 2013	Turkey	Blunt dissection	Microdebrider	Not stated
Korkmaz 2008	Turkey	Blunt dissection	Blunt dissection	Not stated
Chan 2004	USA	Electrocautery	Coblation	Not stated
Chang 2005	USA	Electrocautery	Coblation	99
Chang 2008	USA	Coblation	Coblation	Not stated
Coticchia 2006	USA	Electrocautery	Radiofrequency	100
Derkay 2006	USA	Electrocautery	Microdebrider	Not stated
Park 2007	USA	Electrocautery	Electrocautery	100
Sobol 2006	USA	Electrocautery	Microdebrider	100