Mohammed T. Abou-Saleh

CASE-CONTROL STUDIES 203centre (Liverpool) with a different design and funded earlier.Each of the five centres obtained a stratified random samplefrom Family Health Service Authority lists of sufficientindividuals aged 65 years and over to achieve at least 2500interviews (see Figure 1 for the study design). The Liverpoolstudy consisted of a sample of 6035 individuals aged 65 yearsand over, stratified by sex and 5 year age bands. 5222 receiveda detailed assessment interview, with a selection also receivingthe same interview by a clinician 3 months later. This processwas repeated at 2 and 4 years. At 7–8 years the cohort wasreinterviewed using the five-centre combined screen andassessment interview.BRAIN DONATIONAt all waves of the study, selected participants and theirfamilies have been approached with a request to considerdonating brain tissue after death. Procedures are in place tocollect, process and examine brains from these individuals,which are stored locally. There are currently 347 brains withinCambridgeGwyneddNewcastleNottinghamOxfordLiverpool2 3 4 5 6 7 8 9 10 11 12Prevalence (%)Figure 3. Prevalence estimates with 95% confidence intervals forAGECAT organicity O3+. From reference 3, with permissionTable 1. Estimated numbers of cognitively impaired or disabled elderlypeople in England and Wales by age group, sex and type of disabilityTownsend disability grouping (%)100806040200Men