Kamal 2003.

Methods	RCT. Double‐masked. Placebo controlled.
Participants	356 participants with OHT. Racial constitution is not reported. Inclusion criteria: IOP between 22 and 35 mmHg, normal visual field. Exclusion criteria: systemic beta‐blockers, diabetes mellitus.
Interventions	Betaxolol 0.5% twice daily. Placebo.
Outcomes	Incidence of reproducible glaucomatous visual field defect.
Notes	Median follow‐up time 60 months (for those completing the trial). 102 drop‐outs: 48 betaxolol group (8 local and 3 systemic adverse effects), 53 placebo group (7 local, and 4 systemic adverse effects). Intent‐to‐treat analysis.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Low risk	A ‐ Adequate