ABSTRACT
OBJECTIVES: Therapists have long observed a phenomenon referred to as the 'revolving door' of mental health services, in which individuals often develop, seek treatment for, and recover from multiple mental illnesses across their life. However, this has not been systematically examined. If this phenomenon is widespread, one would expect that the number of lifetime disorders would exceed that of current disorders. The aim of this meta-analysis was to test this hypothesis. METHODS: A search was conducted of the following databases: MEDLINE, PsycINFO and Web of Science. In total, 38 studies were included in the current review; 27 of these contained sufficient quantitative data to be included in the meta-analysis, addressing the primary research aim. The remaining 11 studies were included in the systematic review only. RESULTS: Meta-analyses of the 27 studies indicated that the average number of lifetime disorders was 1.84 times that of current disorders. Previous treatment significantly moderated this relationship, while the clinical nature of the sample did not. Examination of the remaining studies revealed common temporal sequences, indicating disorders which typically develop first or consequently to other disorders. CONCLUSIONS: These findings provide support for the revolving door of mental illness, suggesting a need for transdiagnostic treatments and broader conceptualisation of relapse prevention.