. 2017 Jun 13;29(3):199–203. doi: 10.1016/j.joco.2017.05.007

Table 4.

Difference in mean absolute error between intraocular lens (IOL) formulas within the same vergence.

Vergence	Formula (a)	Formula (b)	Difference (a−b)	Standard error^a	P-value^a	95% Confidence interval^a		P-value^b
Vergence	Formula (a)	Formula (b)	Difference (a−b)	Standard error^a	P-value^a	Lower limit	Upper limit	P-value^b
Axial Length (D)	Hoffer Q	Holladay I	0.14	0.06	0.026	0.03	0.25	0.040
		SRK/T	0.30	0.14	0.039	0.03	0.57	0.096
		SRK II	0.37	0.16	0.030	0.08	0.69	0.064
	Holladay I	SRK/T	0.16	0.09	0.087	−0.01	0.33	0.096
	Holladay I	SRK II	0.23	0.12	0.064	0.00	0.45	0.085
	SRK/T	SRK II	0.07	0.06	0.249	−0.05	0.18	0.290
Refractive (D)	Lanchulev	Holladay R	2.00	0.25	0.002	1.48	2.45	<0.001
		Khan	2.76	0.37	0.002	1.97	3.45	<0.001
		Mackool	2.78	0.41	0.001	1.88	3.48	<0.001
	Holladay R	Khan	0.76	0.18	0.001	0.39	1.12	0.001
	Holladay R	Mackool	0.78	0.21	0.002	0.37	1.21	0.002
	Khan	Mackool	0.02	0.08	0.810	−013	0.17	0.702

D: Diopter; a: Bootstrap output; b: P-value from Wilcoxon signed rank test.

P-value less than 0.05 was statistically significant.