1. Included participants, definition of portal hypertension, grading of varices and type of intervention.

Trial	Definition of portal hypertension	Size of oesophageal varices	Primary prevention	Secondary prevention	Proportion of participants for primary/secondary prevention
Agarwala 2011	Endoscopically verified oesophageal varices	Not defined	Yes	Yes	Unclear
Bañares 2002	Endoscopically verified oesophageal varices and a basal hepatic venous pressure gradient > 12 mmHg	Small or large (classification not defined)	Yes	No	100%/0%
De 2002	Endoscopically verified oesophageal varices and a basal hepatic venous pressure gradient ≥ 12 mmHg	Varices < grade 2 according to Japanese Research Society for Portal Hypertension	Yes	Yes	61%/39%
ElRahim 2018	Endoscopically verified oesophageal varices	Medium or large (classification not defined)	Yes	No	100%/0%
Gupta 2016	Endoscopically verified oesophageal varices and a basal hepatic venous pressure gradient > 12 mmHg	Grade 2‐4 as described in Paquet 1982	No	Yes	0%/100%
Hanno 2016	Endoscopically verified oesophageal varices	Grade 3 or 4	Not described	Not described	Not described
Hobolth 2012	Endoscopically verified oesophageal varicesa and a basal hepatic venous pressure gradient ≥ 12 mmHg	Grade 1 to 3 as described in Baveno III	Yes	Yes	74%/26%
Kim 2016	Endoscopically verified oesophageal varices and a basal hepatic venous pressure gradient > 12 mmHg	Grade 2 or 3 according to Beppu 1981	Yes	No	100%/0%
Lo 2012	Endoscopically verified oesophageal varices	Grade 1‐3 according to Baveno III	No	Yes	0%/100%
Mo 2014	Endoscopically or CT scan‐verified oesophageal varices and a basal hepatic venous pressure gradient > 5 mmHg	Not defined (no endoscopic classification used)	Yes	Yes	48%/52%
Wei 2018	Endoscopically verified oesophageal varices	Not defined (classification not defined)	No	Yes	0%/100%

^aA subgroup of 12 participants had a HVPG > 12 mmHg but did not have oesophageal varices; we excluded this subgroups from our analyses