Kao 1997.

Methods	Study design: randomized controlled trial, parallel group Unit of analysis: eyes Number randomized: 15 eyes (of 14 participants), 7 eyes in the MMC group, 8 eyes in EX‐DCR alone group Number of arms: 2 Enrollment start year: 1994 Length of follow‐up: 6 months Sample size calculations: not reported Losses to follow‐up: none
Participants	Country: Taiwan Age (mean (SD)): 55 (9.5) in the MMC group, 52 (14.7) in the EX‐DCR alone group Females (n (%)): not reported Inclusion criteria: patients with primary acquired nasolacrimal duct obstruction Exclusion criteria: not reported Study group differences: not reported
Interventions	Intervention: EX‐DCR with 0.2 mg/mL MMC application during surgery Comparison intervention: EX‐DCR alone
Outcomes	Measured outcomes: functional success, defined as the relief of epiphora anatomic success, defined as patency to lacrimal irrigation ostium size on nasal endoscopy postoperatively complications Adverse events: septo‐osteotomy adhesion
Identification	Author name: Shine CS Kao Institution: National Taiwan University Hospital Email: not reported
Notes	Funding source: not reported Declarations of interest: not reported Trial registration number: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method of random sequence generation was not reported.
Allocation concealment (selection bias)	Unclear risk	Allocation concealment was not reported.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Masking of participants and personnel was not reported.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All the calculations were done by one of our staff members who did not know whether he was looking at a photograph of a mitomycin C group or a control group patient." Masking of other outcome assessors was not reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	There were no missing outcome data.
Selective reporting (reporting bias)	Unclear risk	No trial or protocol registration available for comparison to ascertain selective outcome reporting.
Other bias	Unclear risk	There was insufficient information to permit a judgement of 'low risk' or 'high risk'.