Demographic factors have been shown to predict the outcome of short-term psychotherapy in the treatment of depressive and anxiety disorders. So far, however, information on the prediction for long- term therapy is missing. to be able to choose an optimal psychotherapy length for the patient, it is essential to know, which demographic factors predict different outcome in short- and long-term therapy.

To compare the prediction of demographic factors on changes in psychiatric symptoms in short- and long-term psychotherapy.

In the Helsinki Psychotherapy Study, 326 psychiatric outpatients, aged 20-46 years, and suffering from depressive or anxiety disorders, were randomly assigned to short-term therapy (short-term psychodynamic psychotherapy or solution-focused therapy combined) or long-term psychodynamic psychotherapy. the demographic factors (i.e. age, gender, education, income, and living arrangement) were assessed at baseline by a questionnaire. Psychiatric symptoms were assessed with the Symptom Check List, Global Severity Index (SCL-90-GSI) at baseline and 7 times during a 3-year follow-up.

Demographic factors were found to predict symptom development during follow-up irrespective of baseline symptom level. Female gender, being aged 25 or more, living with a spouse/partner, high education, and medium level personal income predicted benefiting sufficiently from short-term therapy, whereas being aged under 25, medium education, and living with other(s) than a partner or child(ren) predicted the need of long-term therapy.

Demographic factors may be a useful tool in the selection of patients for short- and long term therapy.