Effectiveness of short-term psychodynamic group therapy in a public outpatient psychotherapy unit

Short-term psychodynamic group therapy in heterogeneous patient groups is common in the public Danish psychiatric system but is in need of evaluation.

To investigate improvement in 39-session psychodynamic group therapy using three criteria: 1) effect size (Cohen's d), 2) statistically reliable improvement, and 3) clinical significant change (CSC).

Pre-post treatment naturalistic design based on 236 outpatients with diagnoses of mood (9.7%), neurotic (50.8%), and personality disorders (39.4%). Symptom change was evaluated on the SCL-90-R Global Severity Index (GSI) and subscales. Analyses were conducted on the total sample and after exclusion of 32 GSI pre-treatment no-cases.

The total sample GSI effect size was 0.74 indicating a moderate to large effect size (ranging from 0.67 in depressed to 0.74 in neurotic and personality disorder patients), which increased to 1.02 after exclusion of pre-treatment no-cases (ranging from 0.98 to 1.11 in depressed and personality disorder patients, respectively). However, in the GSI pre-treatment case sample, 43.1% were unchanged or deteriorated, 27% reliably improved and 29.9% obtained CSC status (ranging from 23.8% of the neurotic to 42.9% of the depressed patients).

Short-term psychodynamic group therapy is associated with medium to large or large effect sizes. However, even though many of the patients reliably improve, a substantial part of the patients are still, after therapy, within the pathological range compared with Danish norms.

Patients referred to public outpatient treatment settings may need alternative or longer treatment than 39 sessions of psychodynamic group therapy over 3 months.