EFO_0004541 (HbA1c measurement) is a quantification of glycated A1c hemoglobin in blood used as an index for blood glucose level over several months. Also known as: A1C measurement, A1c measurement, Glycosylated Hemoglobin, Glycosylated Hemoglobin Measurement, HBA1C, HbA1c levels, Hemoglobin A1C, glycated hemoglobin levels.