Abstract:AIM: To compare the difference and agreement of KR-1W and iTrace for measurement of high order aberrations. METHODS: KR-1W and iTrace were respectively used in a group of healthy people (40 volunteers, 32 eyes) to measure the high order aberration (HOA) of corneal, internal and total ocular. The clinical difference and agreement of two instruments were respectively evaluated by paired-samples t-test and Bland-Altman analysis. RESULTS: The paired-samples t-test showed that the corneal HOA measured by the two instruments had no statistical differences (P＞0.05); but the internal and total ocular HOA had significant statistical differences (P＜0.05), and the mean results measured by iTrace were higher than that of KR-1W. However, Bland-Altman analysis revealed that the HOA of corneal and internal were all in 95% limits of agreement; and just one point of total ocular HOA was beyond the 95% limits of agreement. CONCLUSION: KR-1W and iTrace were consistent well in the measurement of corneal, internal and total ocular HOA, especially for the cornea.
