The Diabetes Screening Study
The study was designed to determine whether a glycosylated hemoglobin level (HgA1c) can be used in place of an oral glucose tolerance test (OGTT) to diagnose diabetes. An augmented MEDLINE search was performed to identify all reports in the literature from 1966 through June 1994 in which glycosylated hemoglobin levels were measured concurrently with performance of OGTTs in the same study. The corresponding authors were contacted and asked to provide individual data for all subjects tested. A total of 31 investigators representing 34 possible studies responded, and 18 were able to provide us with the data requested. Overall fasting plasma glucose concentrations (Fasting), 2-hour post dextrose glucose concentrations, and glycosylated hemoglobin levels were available from 11,276 individuals. A separate assessment of diabetes status (1 = yes, 0 = no) was available on 6219 subjects, and these are the subjects included.
The variables included are:
Study: a study number corresponding to the source of the data HgA1c: glycosylated hemoglobin level in mg/dl Fasting: fasting plasma glucose concentrations in mg/dl OGTT: oral glucose tolerance test in mg/dl Diabetes: presence of diabetes (1 = yes, 0 = no)
The definition (gold standard) for diabetes according to the World Health Organization is a fasting value of 8 mmol/l (143.6 mg/dl) or above 11 mmol/l (197.4 mg/dl) two hours after a 100 g oral glucose load, or on one occasion if the patient has symptoms and on two occasions if he or she does not.
Reference
Peters, Anne L., Mayer B. Davidson, David L. Schriger, Vic Hasselblad, "A Clinical Approach for the Diagnosis of Diabetes Mellitus: An Analysis Using Glycosylated Hemoglobin Levels," Obstetrical & Gynecological Survey, Vol. 52, No. 7, pp. 400-402, 1997.