Imprecision of new criteria for the oral glucose tolerance test.

Subjects selected from a centre specializing in diabetes detection have been classified using nine different methods of diagnosis including the recent criteria of the National Diabetes Data Group and the World Health Organization. The applicability of these two new criteria have been evaluated and compared with seven other previous criteria. The agreements and discrepancies between these criteria have been assessed. Application of the new criteria result in a major redistribution of subjects with abnormal glucose tolerance into a rare category of diabetes mellitus and a large category of 'impaired glucose tolerance'. An important percentage of our population (33%) is excluded from the three clinical classes circumscribed by the criteria of the National Diabetes Data Group. Among these subjects, two-thirds correspond to the subjects named 'non-diagnostic' by these authors and one-third are not classifiable. The need to allow for all possible oral glucose tolerance test responses is emphasized.