Metcalfe 1989.

Methods	Study design: prospective, randomized, double‐masked, parallel‐group RCT Country: UK Number randomized: Total: 100 Per group: acetazolamide = 50; placebo = 50 Exclusions after randomization: N/A Number analyzed: Total: 100 Per group: acetazolamide = 50; placebo = 50 Unit of analysis (participants vs eyes): eyes, 1 eye per participant, chosen if that eye needed laser. If both eyes were lasered, the first eye was chosen for inclusion. Losses to follow‐up: N/A How was missing data handled?: not reported Reported power calculation: no Unusual study design?: no
Participants	Age (mean ± SD; years): acetazolamide = 74.0 ± 6.0, placebo = 74.6 ± 5.9 Females: acetazolamide = 54%, placebo = 52%, overall = 53% Inclusion criteria: uncontrolled OAG with IOP > 21 mmHg and progressive visual field loss, on maximum tolerated topical therapy, no previous LTP Exclusion criteria: already receiving acetazolamide Equivalence of baseline characteristics: yes
Interventions	Intervention 1: acetazolamide (2 × 250 mg tablets), 1 hour prior to LTP Intervention 2: placebo (2 placebo tablets), 1 hour prior to LTP Length of follow‐up: Planned: 2 months Actual: 2 months
Outcomes	Primary outcomes: IOP in both eyes, degree of anterior segment inflammation Secondary outcomes: not reported Adverse events reported: no Intervals at which outcomes assessed: 30 min; 1, 2, 3, 24 hours; 2 months after laser treatment
Notes	Trial registration: not reported Funding sources: none reported Disclosures of interest: none Study period: not reported Reported subgroup analyses: no
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomization sequence not described.
Allocation concealment (selection bias)	Unclear risk	Allocation concealment not reported.
Masking of participants and personnel (performance bias)	Low risk	"The medication selected was masked to both the patient and the physician."
Masking of outcome assessment (detection bias)	Unclear risk	No information on efforts to mask the outcome assessors reported.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear whether there were any 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