title: Impact of literacy and years of education on the diagnosis of dementia: A population-based study.
abstract: BACKGROUND
  The effect of different educational indices on clinical diagnosis of dementia requires more investigation.
  
  
  OBJECTIVE
  We compared the differential influence of two educational indices (EIs): years of schooling and level of education (i.e., null/low literacy, can read and write, primary school, and secondary school) on global cognition, functional performance, and the probability of having a dementia diagnosis.
  
  
  METHODS
  A total of 3,816 participants were selected from the population-based study of older adults "Neurological Disorders in Central Spain" (NEDICES). The 37-item version of the Mini-Mental State Examination (MMSE-37) and the Pfeffer's questionnaire were applied to assess cognitive and functional performance, respectively. The diagnosis of dementia was performed by expert neurologists according to Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) criteria. Logistic regression models adjusted for potential confounders were carried out to test the association between the two EIs and dementia diagnosis.
  
  
  RESULTS
  Both EIs were significantly associated with cognitive and functional scores, but individuals with null/low literacy performed significantly worse on MMSE-37 than literates when these groups were compared in terms of years of schooling. The two EIs were also related to an increased probability of dementia diagnosis in logistic models, but the association's strength was stronger for level of education than for years of schooling.
  
  
  CONCLUSIONS
  Literacy predicted cognitive performance over and above the years of schooling. Lower education increases the probability of having a dementia diagnosis but the impact of different EIs is not uniform.
authors.affiliation: a Department of Basic Psychology , Psychobiology and Methodology of Behavioral Science, University of Salamanca , Salamanca , Spain.
authors.forename: Israel
authors.initials: I
authors.lastname: Contador
authors.affiliation: b Alzheimer Project Research Unit, Fundación CIEN , Madrid , Spain.
authors.forename: Teodoro
authors.initials: T
authors.lastname: Del Ser
authors.affiliation: c Department of Neurology , University Hospital "12 de Octubre ," Madrid , Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Llamas
authors.affiliation: c Department of Neurology , University Hospital "12 de Octubre ," Madrid , Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Villarejo
authors.affiliation: c Department of Neurology , University Hospital "12 de Octubre ," Madrid , Spain.|d Faculty of Medicine , Complutense University , Madrid , Spain.|e The Biomedical Research Centre Network for Neurodegenerative Diseases (CIBERNED), Carlos III Research Institute , Madrid , Spain.
authors.forename: Julián
authors.initials: J
authors.lastname: Benito-León
authors.affiliation: d Faculty of Medicine , Complutense University , Madrid , Spain.|e The Biomedical Research Centre Network for Neurodegenerative Diseases (CIBERNED), Carlos III Research Institute , Madrid , Spain.|f Research Institute, Hospital "12 de Octubre" (i+12) , Madrid , Spain.
authors.forename: Félix
authors.initials: F
authors.lastname: Bermejo-Pareja
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition / Q000502:physiology*; D003704:Dementia / Q000175:diagnosis* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004522:Educational Status; D005260:Female; D006801:Humans; D000067010:Literacy; D008297:Male; D008875:Middle Aged; D013030:Spain; D011795:Surveys and Questionnaires
keywords: Aging; Cognitive reserve; Diagnosis; Education; Neuropsychology