Table 4.

Comparison of the corneal higher-order image difference HOAS of the three groups [x̅ ± s].

Group	Number of subjects	Pre-op	1 month post-op	3 months after operation
SMILE group	200	0.28 ± 0.08	0.96 ± 0.11	0.97 ± 0.14
FS-LASIK group	200	0.27 ± 0.06	0.48 ± 0.84	0.47 ± 0.10
SBK group	200	0.28 ± 0.07	0.59 ± 0.95	0.61 ± 0.98
F	-	1.340	23.420	40.320
P value	-	0.262	0.001	1.1