Table 4.

Refractive outcomes in the very short eyes, 22.0 mm and shorter (n = 42)

Formula	Optimized constant	MPE ± SD (D)	MedAE (D)	MAE (D)	MaxAE (D)	PE (%) <
						0.25 D	0.50 D	0.75 D	1.00 D
New formulas
B II	2.00	0.08 ± 0.443	0.35	0.38	1.02	39.5	72.1	93.0	97.7
BTAL	1.97	−0.09 ± 0.419	0.32	0.36	0.86	38.1	72.4	95.2	100.0
EVO	119.12	−0.13 ± 0.400	0.33	0.35	0.87	38.1	76.1	95.2	100.0
Hill-RBFa	119.22	0.24 ± 0.430	0.32	0.40	1.14	33.3	69.1	88.1	95.2
Hoffer QST	5.72	−0.02 ± 0.420	0.36	0.36	0.95	33.3	76.2	95.2	100.0
HOL2	5.65	−0.13 ± 0.452	0.37	0.41	1.09	30.9	66.7	92.9	97.6
HOL2-NLR	5.64	−0.10 ± 0.452	0.36	0.40	1.13	23.8	71.4	97.6	97.6
K6	119.22	0.13 ± 0.401	0.26	0.33	1.02	47.6	76.2	95.2	97.6
Kane	119.19	0.04 ± 0.429	0.36	0.36	1.03	35.7	69.1	95.2	97.6
Olsen	4.74	0.04 ± 0.422	0.34	0.35	0.88	40.5	73.8	92.9	100.0
P-DGS	118.60	−0.04 ± 0.331	0.27	0.33	0.86	45.2	76.2	95.2	100.0
T2	119.24	0.03 ± 0.439	0.35	0.36	0.92	33.3	73.8	90.5	100.0
VRF	5.70	−0.04 ± 0.434	0.35	0.37	1.04	28.6	76.2	95.2	97.6
Traditional formulas
Haigis	b	0.06 ± 0.479	0.38	0.40	1.10	34.9	69.8	88.4	97.7
Hoffer Q	5.75	−0.07 ± 0.474	0.42	0.40	0.81	25.6	67.4	86.0	100.0
Holladay 1	1.98	0.06 ± 0.444	0.39	0.38	0.93	27.9	76.7	93.0	100.0
SRK/T	119.25	−0.03 ± 0.443	0.26	0.36	0.98	46.5	72.1	90.7	98.7

B II = Barrett Universal II; BTAL = Barrett True Axial Length; EVO = Emmetropia Verifying Optical; HOL2 = Holladay 2; HOL2-NLR = Holladay 2 with the nonlinear regression; MAE = mean absolute error; MaxAE = maximal absolute error; MedAE = median absolute error; MPE = mean prediction error; P-DGS = PEARL-DGS; PE = prediction error

^aOnly 71 eyes were measured, with 7 eyes out of bounds of the pattern recognition grid

^bHaigis constants (a0 = 0.623, a1 = 0.323, and a2 = 0.149)