Table 2.

Prediction outcomes of the BUII, EVO 2.0, Kane, Pearl-DGS, RBF 3.0 and Zhu-Lu formulas in highly myopic eyes

Parameters	BUII	EVO 2.0	Kane	Pearl-DGS	RBF 3.0	Zhu-Lu	P value
Internal test dataset (n = 361)
PE (D)
Mean	− 0.11	− 0.14	− 0.31	0.14	− 0.10	0.005
SD	0.54	0.56	0.55	0.71	0.51	0.46
MAE ± SD (D)	0.46 ± 0.30	0.46 ± 0.34	0.49 ± 0.39	0.55 ± 0.47	0.38 ± 0.35	0.34 ± 0.31
MedAE (D)	0.43*	0.40*	0.40*	0.45*	0.29	0.26	< 0.001
IOL formula performance index	0.048	0.048	0.056	0.040	0.065	0.071
External test dataset (n = 150)
PE (D)
Mean	− 0.01	− 0.02	− 0.21	0.20	− 0.06	0.05
SD	0.57	0.53	0.52	0.53	0.57	0.50
MAE ± SD (D)	0.43 ± 0.38	0.40 ± 0.35	0.45 ± 0.34	0.45 ± 0.34	0.44 ± 0.37	0.38 ± 0.34
MedAE (D)	0.34	0.32	0.37*	0.40*	0.36*	0.30	0.001
IOL formula performance index	0.063	0.063	0.052	0.050	0.056	0.063

BUII = Barrett Universal II; EVO = Emmetropia Verifying Optical; RBF = Radial Basis Function; PE = prediction error; SD = standard deviation; D = diopters; MAE = mean absolute error; MedAE = median absolute error; IOL = intraocular lens

^*P < 0.05 when compared with the Zhu-Lu formula using the Friedman test with Bonferroni post hoc analysis