title: Epidemiological usefulness of population-based electronic clinical records in primary care: estimation of the prevalence of chronic diseases.
abstract: BACKGROUND
  Chronic health problems are the main cause of disease, disability and death in developed countries, and their prevalence is increasing.
  
  
  OBJECTIVE
  To estimate the prevalence of selected chronic illnesses based on electronic clinical records in primary care (ECRPC) and to assess its usefulness for epidemiological research, by comparing ECRPC data against those reported by a contemporary health survey.
  
  
  METHODS
  
  
  
  METHODS
  Descriptive cross-sectional study.
  
  
  METHODS
  All primary care medical consultations in the Madrid Regional Public Health System (PHS).
  
  
  METHODS
  A total of 23 535 182 ECRPC-registered episodes of illness, generated by PHS patients over 15 years of age seeking medical care during 2005-06.
  
  
  METHODS
  Prevalences of chronic diseases estimated on the basis of medically examined cases registered in ECRPC and morbidity as reported by a contemporary health survey covering the same geographic area.
  
  
  RESULTS
  A total of 52.5% of the adult population had some chronic health problem. The highest overall prevalences were hypertension (14.8%), mental disorders (12.0%) and allergy (11.6%). Prevalences were generally highest among women, elderly and the native population. Depending on the specific disease, ECRPC-based prevalences were similar to (e.g. diabetes), higher (e.g. chronic skin problems) or lower (e.g. asthma and dyslipidaemia) than those reported by surveys, with certain age- and sex-related variations.
  
  
  CONCLUSIONS
  Prevalences estimated from ECRPC and survey data present variations depending on the disease, age and sex. Both data sources provide complementary information about chronic disease prevalence. ECRPC have the advantage of generating an ongoing standardized register and entailing no additional effort for health professionals.
authors.affiliation: Institute of Public Health, Madrid Regional Health Affairs Authority, Madrid, Spain. maria.estebanv@salud.madrid.org
authors.forename: M D
authors.initials: MD
authors.lastname: Esteban-Vasallo
authors.forename: M F
authors.initials: MF
authors.lastname: Domínguez-Berjón
authors.forename: J
authors.initials: J
authors.lastname: Astray-Mochales
authors.forename: R
authors.initials: R
authors.lastname: Gènova-Maleras
authors.forename: A
authors.initials: A
authors.lastname: Pérez-Sania
authors.forename: L
authors.initials: L
authors.lastname: Sánchez-Perruca
authors.forename: M
authors.initials: M
authors.lastname: Aguilera-Guzmán
authors.forename: F J
authors.initials: FJ
authors.lastname: González-Sanz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002908:Chronic Disease / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D016347:Medical Records Systems, Computerized; D008875:Middle Aged; D011159:Population Surveillance / Q000379:methods*; D015995:Prevalence; D011320:Primary Health Care; D013030:Spain / Q000453:epidemiology; D055815:Young Adult