RESUMO
PURPOSE: To evaluate prediction accuracy of formulas included in the ESCRS-Online-IOL-Calculator using standard keratometry (K) or total keratometry (TK). SETTING: Hospital-based academic practice. DESIGN: Retrospective case-series. METHODS: Participants: 523 cataract patients (523 eyes). Outcome Measures: trimmed-means of the spherical equivalent prediction error (SEQ-PE, trueness), precision and absolute SEQ-PE (accuracy) of all seven formulas available on the ESCRS-Online-IOL-Calculator as well as the mean (Mean-All) and median (Median-All) of the predicted SEQ refraction of all formulas. Sub-group analyses evaluated the effect of axial length on formula accuracy. RESULTS: Trimmed-mean SEQ-PE range of all formulas varied from -0.075 to +0.071D for K-based and from -0.003 to +0.147D for TK-based calculations, with TK-based being more hyperopic in all formulas (p<0.001). Precision ranged from 0.210 to 0.244D for both K-based and TK-based calculations. Absolute SEQ-PE ranged from 0.211 to 0.239D for K-based and from 0.218 to 0.255D for TK-based calculations. All formulas, including Mean-All and Median-All, showed high accuracy with 84-90% of eyes having SEQ-PEs within 0.50D.Myopic trimmed-mean SEQ-PEs significantly different from zero were observed in long eyes for Pearl DGS (-0.110D, p=0.005), Hill RBF (-0.120D, p<0.001) and Hoffer QST (-0.143D, p=0.001), and in short eyes for EVO 2.0 (-0.252D, p=0.001), Kane (-0.264D, p=0.001), Hoffer QST (-0.302D, p<0.001), Mean-All (-0.122D, p=0.038) and Median-All (-0.125D, p=0.043). CONCLUSION: Prediction accuracy of all ESCRS IOL Calculator formulas was high and globally comparable. TK-based calculations did not increase prediction accuracy and tended towards hyperopia. Observations indicating formula superiority in long and short eyes merit further evaluation.