However, we are not aware of any comprehensive review of both the causes and consequences of nonadherence in schizophrenia. Furthermore, there is a need for a review that investigates whether the data allow for a quantitative assessment of the specific link between nonadherence and hospitalization. The objective of this study was to perform a systematic review of Inhibitors,research,lifescience,medical the factors that influence adherence in schizophrenia and of the consequences of nonadherence for the patient, healthcare system and society. Particular attention was given to the effect of nonadherence on hospitalization rates, as a key driver of increased

costs of care. Methods A systematic Brefeldin A mouse literature review was conducted to include English-language manuscripts published from 2000 in OVID. Four electronic databases (MEDLINE, MEDLINE In-Process, EMBASE and the Cochrane Library) were searched to identify potentially relevant articles. Conference abstracts were not included in this review. The search combined free Inhibitors,research,lifescience,medical text and medical subject headings (MeSH) disease terms with adherence terms for psychosis or schizophrenia AND adherence or compliance or persistence. As the outcomes of interest included all factors and consequences of nonadherence, no search terms were included for specific outcomes, as this may have resulted in missing some

outcomes. One search was conducted for both sets of outcomes. Thus a very Inhibitors,research,lifescience,medical broad search strategy was adopted in order to avoid missing potentially relevant information, with the identification of relevant studies Inhibitors,research,lifescience,medical per outcome (i.e. nonadherence drivers or consequences) based on abstract screening [Liberati et al. 2009]. The abstract screening for identification of relevant data was based on the following predefined Inhibitors,research,lifescience,medical criteria: populations comprising adult patients with schizophrenia and disorders with psychotic features, psychosis and schizophrenia spectrum disorders; oral antipsychotic interventions were included, and subanalysis of the impact on adherence on hospitalization rates focused on studies of oral interventions comparing once daily dosing with multiple daily dosing;

studies were excluded based on comparison if they were comparing second interventions or drugs which were not of interest; outcomes including factors influencing adherence rates and consequences of nonadherence; study designs including phase II or III randomized controlled trials, observational studies such as prospective and retrospective studies, cross-sectional questionnaire-based studies, economic and epidemiologic studies, meta-analyses and qualitative reviews; and a focus on studies with larger sample sizes and more recent publications (publications after 2001) due to the large expected number of studies identified. Two research facets were assessed qualitatively: drivers of nonadherence and consequences of nonadherence.