Table 5. Parameter coefficients in the optimal model to explain CH or CRF.

	CH		CRF
	R	p value	R	p value
A1 time (ms)	4.6	<0.001	4.2	<0.001
A1 length (mm)			1.9	0.10
A1 deformation amplitude (mm)			20.8	0.13
A2 time (ms)	1.9	<0.001	0.80	0.005
highest concavity deformation amplitude (mm)	3.1	-0.014
CCT (μm)	0.016	<0.001	0.017	<0.001
R2	0.67	<0.001	0.73	<0.001

The optimal model was selected from the variables of age, gender, GAT-IOP, AL, CCT, average corneal curvature, and the CST parameters of deformation amplitude, A 1/2 time, A 1/2 length, A 1/2 velocity, highest concavity time, peak distance and A 1/2 highest concavity deformation amplitude. The second order bias corrected Akaike Information Criterion index was used to select the optimal model. CCT: central corneal thickness, CH: corneal hysteresis, CRF: corneal resistant factor