Aim: To determine a valid numerical score according to the present risk factors for the prediction of impaired glucose tolerance in our patients. Materials and Methods: A total of 502 cases (340 females, 162 mates; mean age: 48.3 +/- 10.3) without overt diabetes aged over 20, whose fasting plasma glucose level were below 126 mg/dl were included in this study. After fasting blood samples were drawn, a 2-h oral glucose tolerance test was performed. Bivariate and multivariate analyses were performed to obtain a numerical score for predicting impaired glucose tolerance using risk factors such as age, sex, positive family history for diabetes, body mass index, waist circumference, blood pressure, triglycerides, HDL cholesterol, and fasting plasma glucose. Results: According to the 2-h plasma glucose levels, impaired glucose tolerance was detected in 96 of the patients, and diabetes was detected in 5 patients, while the remaining 401 patients had normal glycaemic values. Age (>= 50), hypertension, high triglycerides, large waist, body mass index >= 25 kg/m(2), and a fasting plasma glucose level of 100-109 mg/dl, or 110-125 mg/dl were associated with an impaired glucose tolerance (p<0.05). In a 8-point scale formed using these 6 parameters, a score of >= 6 could predict impaired glucose tolerance with a specificity of 99% and positive predictive value of 63%. Conclusion: A numerical score that could be used to predict impaired glucose tolerance in our patients has been proposed with this study.