Patient outcome and guideline conformity in inpatient schizophrenia treatment was systematically evaluated and compared with 597 patients across seven psychiatric hospitals. Patient structure and treatment processes showed a great variability between hospitals. Patient characteristics, especially mental state, and the chronicity of the disease were the strongest predictors of clinical outcome. Outcome evaluation using quality indicators is only possible after case-mix adjustment taking into account prognostic factors. A poorer average clinical outcome was associated with lower guideline conformity in a variety of treatment domains. After case-mix adjustment, benchmarking is an opportunity to improve quality of treatment and promote guideline conformity.