[Undetermined family diagnosis--uncertain diagnosis]

The results of testing convergence- and discriminance-validity of the central dimensions "cohesion" and "control" for family diagnostics and therapy are presented in this paper by means of a multitrait-multimethod matrix which includes five known family diagnostic instruments from seven studies published up until the end of 1995. The main result demonstrates that both discriminance- and convergence-validity cannot be considered safe from "cohesion" or "control".