The purpose of this observational study is to study specific outcomes of interest in users of quetiapine compared with all other atypical antipsychotics and specifically olanzapine and risperidone. The outcomes of interest are all-cause mortality, failed suicide attempts, extrapyramidal symptoms, diabetes mellitus, hypothyroidism, acute myocardial infarction and stroke. This retrospective cohort study is based on population-based record linkage system (PHARMO RLS) capturing about 2.5 millions residents in the Netherlands.