A hematology analyser comprising: a) a flow cell; b) a light source for directing light to said flow cell; c) a plurality of detectors (32, 34, 36) for detecting light scattering by cells of a blood sample moving through the flow cell on a plurality of optical scattering channels; d) a colorimetric transducer for measuring hemoglobin concentration in a cell lysate; e) an impedance transducer for measuring changes in impedance in the blood sample; and f) a data analysis workstation comprising a physical memory containing instructions which, when executed by the workstation, cause the hematology analyzer to: i) calculate the volume of individual red blood cells in a sample containing a population of red blood cells using: intermediate angle scatter and axial light loss optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; and impedance measurements of the individual red blood cells obtained using the impedance transducer, or ii) calculate the hemoglobin content of individual red blood cells in a sample containing a population of red blood cells using: intermediate angle scatter and polarized side scatter optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; impedance measurements of the individual red blood cells obtained using the impedance transducer; and measurements of hemoglobin concentration of the individual red blood cells obtained by the colorimetric transducer. a) a flow cell; b) a light source for directing light to said flow cell; c) a plurality of detectors (32, 34, 36) for detecting light scattering by cells of a blood sample moving through the flow cell on a plurality of optical scattering channels; d) a colorimetric transducer for measuring hemoglobin concentration in a cell lysate; e) an impedance transducer for measuring changes in impedance in the blood sample; and f) a data analysis workstation comprising a physical memory containing instructions which, when executed by the workstation, cause the hematology analyzer to: i) calculate the volume of individual red blood cells in a sample containing a population of red blood cells using: intermediate angle scatter and axial light loss optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; and impedance measurements of the individual red blood cells obtained using the impedance transducer, or ii) calculate the hemoglobin content of individual red blood cells in a sample containing a population of red blood cells using: intermediate angle scatter and polarized side scatter optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; impedance measurements of the individual red blood cells obtained using the impedance transducer; and measurements of hemoglobin concentration of the individual red blood cells obtained by the colorimetric transducer. i) calculate the volume of individual red blood cells in a sample containing a population of red blood cells using: intermediate angle scatter and axial light loss optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; and impedance measurements of the individual red blood cells obtained using the impedance transducer, or intermediate angle scatter and axial light loss optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; and impedance measurements of the individual red blood cells obtained using the impedance transducer, or ii) calculate the hemoglobin content of individual red blood cells in a sample containing a population of red blood cells using: intermediate angle scatter and polarized side scatter optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; impedance measurements of the individual red blood cells obtained using the impedance transducer; and measurements of hemoglobin concentration of the individual red blood cells obtained by the colorimetric transducer. intermediate angle scatter and polarized side scatter optical scattering data of the individual red blood cells obtained by the plurality of the optical scattering channels; impedance measurements of the individual red blood cells obtained using the impedance transducer; and measurements of hemoglobin concentration of the individual red blood cells obtained by the colorimetric transducer.