. 2020 Apr 7;2020(4):CD012309. doi: 10.1002/14651858.CD012309.pub2

Dogan 2013a.

Methods	Study design: randomized controlled trial, parallel group Unit of analysis: eyes Number randomized: 80 in total, 30 in Group 1, 27 in Group 2, 23 in Group 3 Number of arms: 3 Enrollment start year: 2009 Length of follow‐up: 24 months Sample size calculations: not reported Losses to follow‐up: 3 in Group 1, 2 in Group 2, 3 in Group 3
Participants	Country: Turkey Age (mean (SD)): 62 (NR) in total, 63.4 (NR) in Group 1, 60.7 (NR) in Group 2, 61.8 (NR) in Group 3 Females (n (%)): 67 (83.7) in total Inclusion criteria: diagnosis of nasolacrimal canal obstruction Exclusion criteria: nasal pathologies (e.g. polyp, carcinoma, or advanced septal deviation), no previous lacrimal surgery, no history of naso‐orbital trauma Study group differences: not reported
Interventions	Intervention 1: Group 1: endocanalicular DCR (ECL‐DCR) with 0.4 mg/mL MMC application during surgery and silicone intubation Intervention 2: Group 2: ECL‐DCR with silicone intubation Comparison intervention: Group 3: ECL‐DCR with 0.4 mg/mL MMC application during surgery
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 Adverse events: stenosis, premature tube loss, granulation, synechia, infection, hemorrhage
Identification	Author name: Remi Zogan Institution: Bezmialem Vakif University Email: dr.remzidogan@gmail.com
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	Sequence generation was not described in the article.
Allocation concealment (selection bias)	Unclear risk	No allocation concealment described in the study.
Blinding of participants and personnel (performance bias)   All outcomes	Unclear risk	Masking of study personnel and participants was not reported.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	Masking of study outcome assessors was not reported.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	2 failures in Group 1, 3 in Group 2, and 2 in Group 3 were lost to follow‐up.
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'.