The present invention provides a method of determining disease state in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical in the tissue responsive to the excitation light is detected. The HbA1c or FPG measurement of the individual (or other secondary indication of disease state) can also be determined. A model combining the tissue fluorescence and one or more of the secondary indications can be used to determine the disease state of the individual. In some embodiments, the tissue fluorescence can be used as an initial screen, and the combination with secondary indications only made for those individuals for whom the fluorescence screen indicates an increased likelihood of disease.