status of the elderly. J.Clin.Epidemiol. 2002 Oct;55:1007-12. 8. Sousa RM, Ferri CP, Acosta D, Albanese E, Guerra M, Huang Y, Jacob KS, Jotheeswaran AT, Rodriguez JJ, Pichardo GR, et al. Contribution of chronic diseases to disability in elderly people in countries with low and middle incomes: a 10/66 Dementia Research Group population-based survey. Lancet. 2009 Nov 28;374:1821-30. 9. Sousa RM, Ferri CP, Acosta D, Guerra M, Huang Y, Ks J, At J, Guerra Hernandez MA, Liu Z, Pichardo GR, et al. The contribution of chronic diseases to the prevalence of dependence among older people in Latin America, China and India: a 10/66 Dementia Research Group population-based survey. BMC Geriatr. 2010 Aug; 6;10:53. Acknowledgements This thematic briefing was prepared for the First WHO Ministerial Conference on the Global Action Against Dementia and was written by Martin Prince, Maelenn Guerchet and Matthew Prina (Global Observatory for Ageing and Dementia Care, King’s College London, UK). © World Health Organization 2015 All rights reserved. This thematic briefing of the World Health Organization is available on the WHO website (http://www.who.int/mental_health/neurology/ dementia/en/). Requests for permission to reproduce or translate this thematic briefing –whether for sale or for non-commercial distribution– should be addressed to whodementia@who.int. This publication does not necessarily represent the decisions or the policies of the Wo Epidemiology of dementia: prevalence and incidence estimates using validated electronic health records from primary care Anna Ponjoan1–3 Josep Garre-Olmo2 Jordi Blanch1 Ester Fages1 Lia Alves-Cabratosa1 Ruth Martí-Lluch1–3 Marc Comas-Cufí1 Dídac Parramon1,4 María Garcia-Gil1 Rafel Ramos1,5 1 Vascular Health Research Group (ISV-Girona), Jordi Gol Institute for Primary Care Research (IDIAPJGol), Barcelona, Catalonia, Spain; 2 Girona Biomedical Research Institute (IDIBGI), Girona, Catalonia, Spain; 3 Santa Clara Primary Care Health Center, Catalan Health Institute, Girona, Catalonia, Spain; 4 Autonomous University of Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; 5 Department of Medical Sciences, School of Medicine, Campus Salut, University of Girona, Girona, Catalonia, Spain Purpose: Updated estimates of incidence and prevalence of dementia are crucial to ensure adequate public health policy. However, most of the epidemiological studies in the population in Spain were conducted before 2010. This study assessed the validity of dementia diagnoses recorded in electronic health records contained in a large primary-care database to determine if they could be used for research purposes. Then, to update the epidemiology of dementia in Catalonia (Spain), we estimated crude and standardized prevalence and incidence rates of dementia in Catalonia in 2016. Methods: The System for the Development of Research in Primary Care (SIDIAP) database contains anonymized information for >80% of the Catalan population. Validity of dementia codes in SIDIAP was assessed in patients at least 40 years old by asking general practitioners for additional evidence to support the diagnosis. Crude and standardized incidence and prevalence (95% CI) in people aged ≥65 years were estimated assuming a Poisson distribution. Results: The positive predictive value of dementia diagnoses recorded in SIDIAP was estimated as 91.0% (95% CI 87.5%–94.5%). Age- and sex-standardized incidence and prevalence of dementia were 8.6/1,000 person-years (95% CI 8.0–9.3) and 5.1% (95% CI 4.5%–5.7%), respectively. Conclusion: SIDIAP contains valid dementia records. We observed incidence and prevalence estimations similar to recent face-to-face studies conducted in Spain and higher than studies using electronic health data from other European populations. Keywords: family physician, accuracy, quality, positive predictive value, electronic medical record, real-world data Introduction Dementia affects about 47 million people worldwide and is related to dependence, poor quality of life, institutionalization, and mortality.1 Age is the main risk factor for dementia, and the world population is aging; therefore, the number of people