[Contributions and difficulties of the social approach in psychiatry: apropos of the American forces in Vietnam and veterans].

The high frequency of the psychiatric manifestations ascertained among american Vietnam veterans contrasts with the low incidence observed during the conflict, at least initially. That one increased from 1969: at the time of the military stalemate and of the progressive withdrawing, which were accompanied with a support of these post-adolescents by their groups and by an unconcerned or divided national opinion, still weaker than previously, on one hand; at the occasion of the spread of drugs, on the other hand. If we only consider the latters, their large availability and the often compensating function which they exerted concurred with an accentuation then observed in the United States. Among others ones, this example shows the difficulties encountered in order to discriminate the different variables, particularly social, which interfere. It is necessary to avoid the danger of generalizations based on small samples, not comparable at all times.