The study examines the effect of different types of antipsychotic treatment on 
the health related quality of life (HRQL) of people with schizophrenia under 
naturalistic outpatient treatment conditions. In a prospective study design, 307 
schizophrenic patients were followed over a period of 2.5 years. HRQL, clinical 
characteristics, and type of antipsychotic medication were assessed five times 
every 6 months. HRQL was assessed by the SF-36. Random effect regression models 
were computed for the SF-36 mental (MCS) and physical (PCS) component scores. 
Propensity scores were included in the regression models to reduce a possible 
sample selection bias. Monotherapeutic treatment with new atypical neuroleptic 
drugs had a more positive effect on the mental health related quality of life 
(MCS) in comparison to treatment with polypharmacological treatment but not with 
oral conventional antipsychotics. Monopharmaceutical treatment with 
depot-antipsychotic drugs had a more positive effect on the physical health 
related quality of life (PCS) in comparison to polypharmacological treatment. 
Study results indicate that atypical antipsychotic drugs are not superior to 
conventional antipsychotics with regard to the effect on QOL. However, 
monopharmaceutical treatment can be assumed to be more effective in improving 
mental and physical related QOL than polypharmaceutical treatment.