Results of Femtosecond Laser-Assisted Descemet Stripping Automated Endothelial Keratoplasty

Table 3

Wilcoxon signed-rank test based on positive ranks.

	VA1W—pre VA	VA2W—pre VA	VA3W—pre VA	VA1M—pre VA	VA2M—pre VA	VA3M—pre VA
Z	−2.842^b	−3.627^b	−3.629^b	−3.624^b	−3.624^b	−3.625^b
Asymp. Sig. (2-tailed)	0.004	0.0001	0.0001	0.0004	0.0003	0.0002
		VA2W-VA1W	VA3W-VA2W	VA1M-VA3W	VA2M-VA1M	VA3M-VA2M
Z		−3.685^b	−3.302^b	−3.638^b	−2.135^b	−3.237^b
Asymp. Sig. (2-tailed)		0.0007	0.001	0.0001	0.033	0.001

b = 1 billion.