Collignon‐Brach 1992.

Methods	RCT. Open label. Active controlled.
Participants	20 people with POAG. Racial constitution is not reported. Inclusion criteria: Untreated IOP of at least 20 mmHg in at least one eye. Exclusion criteria: concomitant ocular or systemic disease.
Interventions	Timolol 0.5% twice daily. Betaxolol 0.5% twice daily.
Outcomes	Change of visual field mean sensitivity, IOP.
Notes	2 years follow up Drop‐out rate is not reported. Authors do not state whether the visual field data are those from one of the eyes, or they did use the mean values of both eyes for analysis.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	B ‐ Unclear