Figure 1From: The impact of mental illness on potentially preventable hospitalisations: a population-based cohort study Selection of study cohorts. Abbreviations: ER = electoral roll registrations, MHCs = mental health clients, MHR = mental health registry. * Non-MHCs matched 2:1 with MHCs by 5-year age group, sex and being a current elector at study entry. The final ratio of non-MHC to MHC was 2.11:1 after excluding MHCs with dementia.Back to article page