Background: It is important to seek cost-effective methods of improving the care and outcome of those with serious mental illnesses. User-held records, where the person with the illness holds all or some personal information relating to the course and care of their illness, are now the norm in some clinical settings. Their value for those with severe mental illnesses is unknown. Objectives: To evaluate the effects of personalised, accessible, user-held clinical information for people with a severe mental illness (defined as psychotic illnesses). Search methods: We updated previous searches by searching the Cochrane Schizophrenia Group Trials Register in August 2011. This register is compiled by systematic searches of major databases, and handsearches of journals and conference proceedings. Selection criteria: We included all relevant randomised controlled trials (RCTs) that: i. have recruited adult participants with a diagnosis of a severe mental illness (specifically psychotic illnesses and severe mood disorders such as bipolar and depression with psychotic features); and ii. compared any personalised and accessible clinical information held by the user beyond standard care to standard information routinely held such as appointment cards and generic information on diagnosis, treatment or services available. Data collection and analysis: Study selection and data extraction were undertaken independently by two authors and confirmed and checked by a third. We contacted authors of trials for additional and missing data. Where possible, we calculated risk ratios (RR) and 95% confidence intervals (CI). We used a random-effects model. We assessed risk of bias for included studies and created a 'Summary of findings' table using GRADE. Main results: Four RCTs (n = 607) of user-held records versus treatment as usual met the inclusion criteria. When the effect of user-held records on psychiatric hospital admissions was compared with treatment as usual in four studies, the pooled treatment effect showed no significant impact of the intervention and was of very low magnitude (n = 597, 4 RCTs, RR 0.99 CI 0.71 to 1.38, moderate quality evidence). Similarly, there was no significant effect of the intervention in three studies which investigated compulsory psychiatric hospital admissions (n = 507, 4 RCTs, RR 0.64 CI 0.37 to 1.10, moderate quality evidence). Other outcomes including satisfaction and mental state were investigated but pooled estimates were not obtainable due to skewed or poorly reported data, or only being investigated by one study. Two outcomes (violence and death) were not investigated by the included studies. Two important randomised studies are ongoing. Authors' conclusions: The evidence gap remains regarding user-held, personalised, accessible clinical information for people with psychotic illnesses for many of the outcomes of interest. However, based on moderate quality evidence, this review suggests that there is no effect of the intervention on hospital or outpatient appointment use for individuals with psychotic disorders. The number of studies is low, however, and further evidence is required to ascertain whether these results are mediated by the type of intervention, such as involvement of a clinical team or the type of information included.