Descriptive data of the centroid location and the area of the 95% error ellipse derived from the covariance matrix together with the spatial median location and the area of the 95% confidence region derived from iterative convex hull stripping.

Data are shown for Keratometry K, Total Keratometry TK, Back Surface measurement BS, and for the differences TK–K and Front Vertex power FV-K for left eyes (OS) and right eyes (OD). The last 2 rows of the table show the respective data for the differences TK–K and FV–K for all eyes. Here the C45 vector components of left eyes were reversed in sign considering symmetry conditions.