Method for determination of the amount of a specific analyte in a sample which may show a prozone effect by photometric assays, wherein the specific analyte is quantified from the change in the optical signal of the reaction mixture after the interaction of the analyte with analyte specific assay reagents, comprising the following steps: a) generating a calibration curve at at least one wavelength and reaction time for the specific analyte of a sample to be determined and depositing the measurement results in a data management system of the instrument platform, b) measuring simultaneously the optical signal for the specific analyte in the sample to be determined at the wavelength used for the determination of the analyte and at least at an additional specific wavelength used for the detection of the prozone effect over the complete reaction time, which is different to the wavelength used for the determination of the analyte, wherein the difference between the wavelength used for the determination of the analyte and at least an additional specific wavelength used for the detection of the prozone effect is higher than 10 nm such that there is improved differentiation of Hook- and non-Hook samples compared to when the same wavelength is used for determination of the analyte and detection of the prozone effect, c) calculating the reaction rate ratio R by using the signals obtained at the wavelength used for the detection of the prozone effect R = reaction rate at time period 2 / reation rate at time period 1 × 100 with reaction rate at time period 2 = signal time point 4 − signal time point 3 / time point 4 − time point 3 and reaction rate at time period 1 = signal time point 2 − signal time point 1 / time point 2 − time point 1 d) judging if a prozone effect is present in the sample by comparison of the calculated ratio value R with predetermined limit values, e) quantifying the amount of the specific analyte by comparison of the optical signal obtained at the wavelength used for the determination of the analyte with the calibration curve. a) generating a calibration curve at at least one wavelength and reaction time for the specific analyte of a sample to be determined and depositing the measurement results in a data management system of the instrument platform, b) measuring simultaneously the optical signal for the specific analyte in the sample to be determined at the wavelength used for the determination of the analyte and at least at an additional specific wavelength used for the detection of the prozone effect over the complete reaction time, which is different to the wavelength used for the determination of the analyte, wherein the difference between the wavelength used for the determination of the analyte and at least an additional specific wavelength used for the detection of the prozone effect is higher than 10 nm such that there is improved differentiation of Hook- and non-Hook samples compared to when the same wavelength is used for determination of the analyte and detection of the prozone effect, c) calculating the reaction rate ratio R by using the signals obtained at the wavelength used for the detection of the prozone effect R = reaction rate at time period 2 / reation rate at time period 1 × 100 with reaction rate at time period 2 = signal time point 4 − signal time point 3 / time point 4 − time point 3 and reaction rate at time period 1 = signal time point 2 − signal time point 1 / time point 2 − time point 1 d) judging if a prozone effect is present in the sample by comparison of the calculated ratio value R with predetermined limit values, e) quantifying the amount of the specific analyte by comparison of the optical signal obtained at the wavelength used for the determination of the analyte with the calibration curve.