OBJECTIVEThe validity of HbA1c as a population diagnostic tool was tested against oral glucose tolerance testing in Abu Dhabi nationals.RESEARCH DESIGN AND METHODSThe screening tool of HbA1c and random glucose was validated against the “gold standard” oral glucose tolerance test according to World Health Organization criteria.RESULTSThe HbA1c threshold of 6.4% provided the optimum balance between sensitivity (72.0%) and specificity (84.3%) with positive and negative predictive values of 47.9 and 93.7% and area under the receiver operating characteristics curve of 0.78. This threshold compares with a threshold of 6.5% recommended by the International Scientific Committee and American Diabetes Association and of 6.3% in a recent study in China.CONCLUSIONSThis study successfully validates the feasibility and threshold of HbA1c for diagnosis of diabetes at the population level in a …