Journal of Child and Family Studies, VoL 1, No. 4, 1992,pp. 371-39i Family Interaction and Child Psychopathology: A Comparison of Two Observation Strategies Mark R. Dadds, Ph.D., 1,3 and Matthew R. Sanders, Ph.D. 2 We examined two systems of assessing family interactions that are in common usage: a home based observation of free parent-child interaction and a clinic based observation of a structured mother-child problem solving discussion. Participants were 18 depressed, 27 conduct disordered and 16 comparison children and their mothers. Results indicated that: 1) these observations may yield very different data about child, and to a lesser extent, parent behavior, 2) parental affect in the clinic was related to their level of aversive behaviour in the home, 3) levels of both aversive and positive behavior for children and their mothers were correlated within each setting, 4) accuracy of diagnostic classifications made on the basis of the observational data were highest for comparison and conduct disordered children, but lowest for depressed children observed in the clinic, and 5) the inclusion of data on mothers" behavior increased classification accuracy for conduct disordered children only. KEY WORDS: family interaction; child; depression; conduct disorder; observation. The last few decades have witnessed increasing interest in the role of the family in the development, maintenance and treatment of child psy- chopathology. The extent to which family structures and interactional processes are causally related to specific forms of childhood psychopathology, however, remains a contentious issue (Goodyer, 1990; Sines, 1987). A pre- requisite for progress in this area is the existence of reliable and valid 1Co-Director for Interventions, Preventive Intervention Research Center for Child Health, Albert Einstein College of Medicine, New York. 2Co-Director, Behaviour Research and Therapy Centre, The University of Queensland, Australia. 3Correspondence should be directed to Mark R Dadds, Preventive Intervention Research Center, Albert Einstein College of Medicine, 1300 Morris Park Ave. NR 7South. Bronx. NY 10461. 371 1062-1024/92/1200-0371506.50/0 © 1992 Human Sciences Press, Inc.