In the last decade cognitive behavioural therapy (CBT) approaches for patients with schizophrenia have been developed, which where especially designed to reduce severity of positive symptoms, readmission rates, treatment non-compliance and disability. Although CBT addresses the key problems of early onset psychoses (EOP)treatment and first evaluations of CBT in adults with schizophrenia are promising, no experience with CBT in adolescents with EOP are available. Therefore the present study is conducted to develop a modified CBT (mCBT) for adolescents with EOP, to explore its acceptance and feasibility and to provide data for a realistic estimation of achievable effect size. Patients are randomized to receive either mCBT+TAU or TAU over a 9 month period. mCBT is an individual outpatient treatment of 20 session and 5 psychoeducational sessions with parents. Follow-ups for two years every 6 months are planned.

Inclusion Criteria:

• Schizophrenia, schizophreniform or schizoaffective disorder (DSM IV 295.1- .9), delusional disorder (DSM IV 297.1)
• Score of 4 or more on one of the PANSS-items P1, P3, G9
• Positive psychotic symptoms for 3 months or more
• Age between 14 and 18
• Fluently German speaking

Exclusion Criteria:

• Diagnosis of delirium, dementia, amnestic or other cognitive disorder, psychiatric disorders due to a somatic factor or related to psychotropic substances according to DSM IV; diseases of the central nervous system
• Alcohol- or drug dependence according to DSM IV
• Verbal IQ < 80
• Travel time to the study centre of more than 1 hour