A method of measuring an analyte amount in a whole blood sample, including (i) measuring the haematocrit level of the whole blood sample; (ii) measuring an analyte amount directly in the whole blood sample; and (iii) calculating a corrected analyte amount according to relation DP=Pa(DST, DH), where Dp, is the corrected analyte amount, DST is the measured analyte amount, DH is the measured haematocrit level, and Pa is a non-constant polynomial of a degree greater than or equal to 1 having as indeterminate values the measured analyte amount, DST, and the measured haematocrit level, DH, and having its polynomial coefficients depending on the analyte.