Costa 1994.

Study characteristics
Methods	Study design: parallel‐group, randomized controlled trial Number randomly assigned: 14 eyes of 14 participants: 9 eyes of 9 participants to laser group and 5 eyes of 5 participants to control group Exclusions after randomization: none reported Losses to follow‐up: none reported Number analyzed: 14 eyes of 14 participants: 9 eyes of 9 participants in laser group and 5 eyes of 5 participants in control group Unit of analysis: participant (1 eye per participant) Handling of missing data: not applicable Sample size and power calculation: not reported
Participants	Country: not reported Mean age: 49 years (range not reported) in the laser group; 47 years (range not reported) in the control group Gender: 7 (78%) men and 2 (22%) women in the laser group; 6 (86%) men and 1 (14%) woman in the control group (potential error in reporting, control group does not add up to 5 participants) Inclusion criteria: pigmentary glaucoma Exclusion criteria: previous intraocular surgery Equivalence of baseline characteristics: not reported
Interventions	Laser: iridotomy using a neodymium:yttrium–aluminum–garnet (Nd:YAG) laser Control: anti‐glaucoma medications in a predetermined order of pilocarpine 1%, beta blockers, and carbonic anhydrase inhibitors Length of follow‐up: Planned: up to 6 months, with extended follow‐up at 2 years Actual: unclear; mean follow‐up was 8 months in the laser group and 10 months in the control group
Outcomes	Outcomes (primary and secondary outcomes not differentiated): visual acuity, mean change in IOP, mean changes in graded pigment dispersion indices (iris transillumination, Krukenberg spindles, trabecular meshwork pigmentation), and mean changes in anterior segment measures (chamber depth and angle) Intervals at which outcomes assessed: 1, 3, 6 months, and 2 years Information on cost of interventions or quality of life: none reported
Notes	Study period: not reported Trial registration: none reported Source of funding: not reported Disclosures of interest: not reported Subgroup analyses: none reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method of randomization not reported.
Allocation concealment (selection bias)	Unclear risk	Method of allocation concealment not reported.
Masking of outcome assessors (detection bias) Visual field	Unclear risk	Visual field not reported as an outcome.
Masking of outcome assessors (detection bias) Intraocular pressure	Unclear risk	Masking of IOP assessors not reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Investigators reported no participants were lost to follow‐up
Selective reporting (reporting bias)	Unclear risk	No protocol or clinical trial registration record was available to assess selective outcome reporting. All outcomes mentioned in the Methods section of the published paper were reported in the Results section
Other bias	Low risk	None identified