September 1981

Outcome of Psychotherapy-Reply

Author Affiliations

Department of Psychiatry 207 Piersol Building G1 Hospital of the University of Pennsylvania Philadelphia, PA 19104

Arch Gen Psychiatry. 1981;38(9):1070. doi:10.1001/archpsyc.1981.01780340122021

We did not discuss causality, nor did we raise the issue of investigating causality by using control groups for patients in the Penn Psychotherapy Project (Archives 1980;37:471-481). These are Dr Loranger's main complaints, which I will do my best to answer.

He is correct that we assumed, but did not prove, that the psychotherapy was a causal agent. In fact, we believe that it was the psychotherapy that had the most important impact. We also readily acknowledge that a small part of the benefits might have been attributable to events in the person's life.

But proving the degree of, or even the existence of, causality is a difficult task—we only know that event A (the treatment) was followed by event B (the outcome). As Dr Loranger and many others have suggested, one approach to the issue of causality would be to compare our treated group with an untreated group.

First Page Preview View Large
First page PDF preview
First page PDF preview