The invention relates to a diagnostic medical device and in particular to a hemoglobin measurement device for measuring hemoglobin content in a blood sample. A hemoglobin sample is prepared from a blood sample by mixing a portion of the blood sample with a diluent and lyse appropriate to release hemoglobin from red blood cells in the blood sample. The sample is then provided to a hemoglobin measurement device (10) where a hemoglobin measurement is made. The device has a chamber (110) with a light source (116) and light detector (118) located at opposite ends and operable at wavelengths that are absorbed or reflected by the hemoglobin. The chamber also includes hemoglobin sample inlet (112) and outlet (114) ports which extend through the body into the measurement chamber.
