Concentrated transdiagnostic and cross-disciplinary micro-choice based group treatment for patients with depression and with anxiety leads to lasting improvements after 12 months: a pilot study

A concentrated transdiagnostic and micro choice-based group treatment for patients with depression and anxiety has previously shown to yield significant reduction in symptoms and increased level of functioning from pre to 3-month follow-up. In the present study, we report the results after 12 months follow-up. This was a non-randomized clinical intervention pilot study, conducted in line with a published protocol. Sixty-seven consecutively referred patients, aged 19–47 (mean age 32.5, SD = 8.0) were included and completed treatment. All had a severity of their problems that entitled them to care in the specialist public mental health care. Self-reported age at onset of symptoms was 17.6 (SD = 7.9) years. Mean number of prior treatment courses was 3.5 (SD = 3.3; range 0–20). The main objective was to assess the treatment effectiveness by questionnaires measuring relevant symptoms at pre-treatment, 7 days-, 3 months-, 6 months- and at 12-months follow-up. Validated measures of functional impairment (WSAS), depression (PHQ9), anxiety (GAD7), worry (PSWQ), fatigue (CFQ), insomnia (BIS) and illness perception (BIPQ) improved significantly (p < .0005) from before treatment to 12 months follow-up, yielding mostly large to extremely large effect sizes (0.89–3.68), whereas some moderate (0.60–0.76). After 12 months, 74