[Compared efficiency of mean corpuscular volume (MCV) and serum gamma-glutamyltransferase (gamma-GT) as screening tests for excess-ethanol drinkers (author's transl)].

53 percent of ethanol drinkers had, before detoxication, a gamma-GT higher than the upper limit of the reference interval at the 2.5 percent risk level (36 mU/ml). 44 percent had a mean corpuscular volume (MCV) higher than the limit (99.2 mum3). In alcoholics not previously "weaned" during a rest cure or in a hospital the proportion becomes 67 percent for gamma-GT but remains at 44 percent for MCV. gamma-GT thus seems a better test for the screening of an excessive ethanol intake than MCV, especially when the subject has not been previously weaned.