One hundred Vietnam-era male veterans in a Veterans Administration. 28-day inpatient alcohol treatment program were classified into combat and noncombat groups according to whether they served in Vietnam or elsewhere during the Vietnam conflict. The MMPI scores of the two groups were compared according to a diagnostic decision-rule developed by Keane, Malloy, and Fairbank in 1984 for posttraumatic stress disorder. Chi-squared analysis showed that the combat group passed the decision-rule in significantly higher numbers than the noncombat group. The results provide evidence that the F-2-8 decision-rule to determine this diagnosis applies to alcoholic as well as nonalcoholic populations.