A method for determining an analyte concentration in a sample, comprising: a) generating at least one output signal from a sample using a biosensor system comprising a measurement device and a sensor strip, b) establishing a reference correlation equation describing a function relating the output signals from the biosensor to analyte concentration values determined from a reference instrument; c) determining a bias in the correlation between analyte concentrations and output signals based on one or more error parameters, wherein: error parameters are parameters that may be measured, calculated or determined through other means and cause errors in the analyte concentration analysis, errors representing the difference between the analyte concentration and an analyte concentration value correlated with the reference correlation equation; wherein the bias is the slope deviation ΔS between the slope from the reference correlation and a hypothetical slope of a line for the output signal value that would provide an analyte concentration in the sample without bias, or a normalized slope deviation; d) determining at least one index function relating the at least one error parameter to the bias; and e) determining the analyte concentration in the sample from the at least one output signal, the reference correlation and the at least one index function. a) generating at least one output signal from a sample using a biosensor system comprising a measurement device and a sensor strip, b) establishing a reference correlation equation describing a function relating the output signals from the biosensor to analyte concentration values determined from a reference instrument; c) determining a bias in the correlation between analyte concentrations and output signals based on one or more error parameters, wherein: error parameters are parameters that may be measured, calculated or determined through other means and cause errors in the analyte concentration analysis, errors representing the difference between the analyte concentration and an analyte concentration value correlated with the reference correlation equation; wherein the bias is the slope deviation ΔS between the slope from the reference correlation and a hypothetical slope of a line for the output signal value that would provide an analyte concentration in the sample without bias, or a normalized slope deviation; error parameters are parameters that may be measured, calculated or determined through other means and cause errors in the analyte concentration analysis, errors representing the difference between the analyte concentration and an analyte concentration value correlated with the reference correlation equation; wherein the bias is the slope deviation ΔS between the slope from the reference correlation and a hypothetical slope of a line for the output signal value that would provide an analyte concentration in the sample without bias, or a normalized slope deviation; d) determining at least one index function relating the at least one error parameter to the bias; and e) determining the analyte concentration in the sample from the at least one output signal, the reference correlation and the at least one index function.