Comparison 1. Mitomycin C dacryocystorhinostomy versus dacryocystorhinostomy alone.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Functional success, defined as the relief of epiphora	20		Risk Ratio (IV, Random, 95% CI)	Subtotals only
1.1 Follow‐up: 6 months	7	356	Risk Ratio (IV, Random, 95% CI)	1.12 [0.98, 1.29]
1.2 Follow‐up: > 6 months	14	909	Risk Ratio (IV, Random, 95% CI)	1.15 [1.07, 1.25]
2 Anatomic success, defined as patency to lacrimal irrigation	14		Risk Ratio (IV, Random, 95% CI)	Subtotals only
2.1 Follow‐up: 6 months	4	306	Risk Ratio (IV, Random, 95% CI)	1.02 [0.95, 1.11]
2.2 Follow‐up: > 6 months	12	831	Risk Ratio (IV, Random, 95% CI)	1.09 [1.04, 1.15]
3 Ostium size on nasal endoscopy	3		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
3.1 Follow‐up: 6 months	2	65	Mean Difference (IV, Fixed, 95% CI)	4.93 [3.40, 6.46]
3.2 Follow‐up: > 6 months	2	100	Mean Difference (IV, Fixed, 95% CI)	2.35 [1.58, 3.12]