Comparison 1. Corneal collagen cross‐linking versus sham or no treatment.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Primary outcomes	2		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected
1.1 Progression (increase in maximal keratometry) at 12 months after treatment	2		Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
1.2 Progression (Increase in maximal keratometry) at 36 months after treatment	1		Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
2 Secondary outcomes	2		Mean Difference (Fixed, 95% CI)	Totals not selected
2.1 Mean maximal keratometry in dioptres at 12 months after treatment	1		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
2.2 Mean uncorrected visual acuity at 12 months after treatment	1		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
2.3 Change in mean corneal thickness (µm) at the thinnest part of the cornea 12 months after treatment	2		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
2.4 Mean average corneal power in dioptres at 12 months after treatment	2		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
2.5 Mean absolute spherical equivalent at 12 months after treatment	1		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]