Birt 1995.

Methods	Study design: parallel‐group RCT Country: US Number randomized: Total: 72 Per group: 2 doses apraclonidine = 24, 1 dose apraclonidine before surgery = 24, 1 dose apraclonidine after surgery = 24 Exclusions after randomization: none Number analyzed: Total: 72 Per group: 2 doses apraclonidine = 24, 1 dose apraclonidine before surgery = 24, 1 dose apraclonidine after surgery = 24 Unit of analysis (participants vs eyes): participants Losses to follow‐up: none reported How was missing data handled?: N/A Reported power calculation: no Unusual study design (any issues with study design)?: potentially not double‐masked, as there was no mention of a vehicle drop given, so participant could have known which group he or she was in based on when the drops were given.
Participants	Age (mean ± SD; years): 2 doses apraclonidine = 70.4 ± 10.6, 1 dose apraclonidine before surgery = 69.3 ± 10.9, 1 dose after surgery = 69.2 ± 9.6 Females: 2 doses apraclonidine = 75%, 1 dose apraclonidine before surgery = 75%, 1 dose apraclonidine after surgery = 54% Inclusion criteria: POAG, including an elevated IOP in the setting of either characteristic glaucomatous optic nerve damage on stereoscopic biomicroscopic exam or glaucomatous visual field defects on Humphrey automated field testing, or both Exclusion criteria: previous treatment over 360° of the angle, unable to return for the 24‐hour IOP check Equivalence of baseline characteristics: yes, no significant difference between the groups in the mean power setting used or in the mean number of burns, or the mean IOP at baseline and between‐group differences were not significant for race, gender, vision, age, and number of medications
Interventions	Intervention 1: 2 doses apraclonidine 1.0%, 15 min before and immediately after the laser procedure Intervention 2: 1 dose apraclonidine 1.0%, 15 min before the laser procedure Intervention 3: 1 dose apraclonidine 1.0%, immediately after the laser procedure Length of follow‐up: Planned: 24 hours Actual: 24 hours
Outcomes	Primary outcomes: IOP at 1 hour and 24 hours after surgery Secondary outcomes: none reported Adverse events reported: no Intervals at which outcomes assessed: baseline; 1, 24 hours
Notes	Trial registration: not reported Funding sources: none reported Disclosures of interest: not reported Study period: 1 September to 30 November 1994 Reported subgroup analyses: no
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"The patients were randomly assigned with the use of a random number table to one of three treatment groups."
Allocation concealment (selection bias)	Unclear risk	Allocation concealment was not reported.
Masking of participants and personnel (performance bias)	Unclear risk	Personnel appear to be masked, "…a second investigator (D.H.S.), who was unaware of the group, assignment, performed the laser treatment…"; however, the report did not mention a vehicle drop given, so the participant could have known to which group (before or after surgery or both) they were assigned.
Masking of outcome assessment (detection bias)	Low risk	"…a third investigator (B.M.), who was also unaware of group assignment, measured the IOP."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear whether there were missing data or how they were handled.
Selective reporting (reporting bias)	Unclear risk	Unclear whether there was selective outcome reporting.
Other bias	Low risk	None