El Sayed 2017.

Study characteristics
Methods	Study design: RCT, parallel‐group design with one study eye per child Number randomized (total and per group): 64 children with 64 eyes; 32 for the microcatheter‐assisted trabeculotomy and 32 for the rigid probe trabeculotomy group Number analyzed (total and per group): 62 eyes in total; 30 eyes in microcatheter‐assisted trabeculotomy group, 32 eyes in rigid probe trabeculotomy group at least 3 months follow‐up Losses to follow‐up: 2 eyes excluded and 3 eyes lost to follow‐up in microcatheter‐assisted trabeculotomy group; two eyes lost to follow‐up in rigid probe trabeculotomy group at two years Length of follow‐up: Planned: 2 years Actual: 2 years Sample size calculation (Y/N): Y (power 80%)
Participants	Country: Egypt Age: microcatheter‐assisted trabeculotomy group: 5.6 ± 4.8 months at surgery; rigid probe trabeculotomy group: 4.4 ± 3.8 months at surgery Gender: microcatheter‐assisted trabeculotomy group: 19/30 (63%) boys and 11/30 (37%) girls; rigid probe trabeculotomy group: 19/32 (59%) boys and 13/32 (41%) girls Inclusion criteria: children under the age of 10 years who required a trabeculotomy for primary congenital glaucoma Exclusion criteria: eyes that underwent previous surgery, eyes requiring combined procedures, and eyes in which the trabeculotomy involved ≤ 120 degrees of Schlemm’s canal Equivalence of baseline characteristics: groups were similar at baseline with respect to eyes (right), gender, age at presentation and age at surgery, cloudy cornea, except corneal diameter (P = 0.02) and cup/disc ratio (P = 0.03)
Interventions	Intervention 1: microcatheter‐assisted trabeculotomy Intervention 2: rigid probe trabeculotomy
Outcomes	Outcomes: Mean IOP Antiglaucoma medications Complete success defined as IOP of < 18 mmHg with no other signs of glaucoma progression C/D ratio Adverse events Intervals at which outcome assessed: 1, 3, 6, 12, and 24 months Issues with outcome assessment: none Adverse effects: yes
Notes	Type of study: published Funding: trial investigator reported that there was no source of funding or conflict of interest (personal communication) Declaration of interest: trial investigator reported that there was no source of funding or conflict of interest (personal communication) Study period: not reported Clinical trial registry: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Children were randomized to undergo 360‐degree trabeculotomy or rigid probe trabeculotomy using a random table.
Allocation concealment (selection bias)	Unclear risk	Method of treatment allocation concealment was not reported. Trial investigator reported: "Participants and their parents were unaware which treatment arm they were assigned to. Patients were randomized to each group using random table," but it is still unclear how allocation was concealed.
Masking of participants and personnel (performance bias)	Unclear risk	Masking of participants and investigators to treatment was not described.
Masking of outcome assessment (detection bias)	High risk	Trial investigator stated that outcome assessors were not masked (personal communication).
Incomplete outcome data (attrition bias) All outcomes	Low risk	2/64 eyes (3%) enrolled were excluded from analysis; 3/30 eyes (10%) and 2/32 (6%) were not included at two years.
Selective reporting (reporting bias)	Unclear risk	No prior protocol or trial registration was available.
Other bias	Low risk	None identified.