title: The validity of a diagnosis of heart failure in a hospital discharge register.
abstract: OBJECTIVE
  The accuracy of a diagnosis of heart failure (HF) in hospital discharge registers is largely unknown. We aimed to determine the validity of such a diagnosis in the Swedish hospital discharge register.
  
  
  RESULTS
  In a population-based study of 2322 middle-aged men (the ULSAM study), 321 participants were diagnosed with HF according to the Swedish hospital discharge register, during a median follow-up time of 29 years. A review board examined the validity of the diagnosis according to the European Society of Cardiology definition of HF. Eighty-two percent of the possible cases were classified as having definite HF. An echocardiographic examination increased the validity to 88%. For patients treated at an internal medicine or cardiology clinic the validity was 86% and 91%, respectively. If HF was the primary diagnosis, the validity was 95%, irrespective of clinic type.
  
  
  CONCLUSIONS
  The HF diagnosis in the Swedish hospital discharge register appears slightly less precise than for acute myocardial infarction and stroke. For population-based research, only those with a primary diagnosis of HF in the hospital discharge register should be regarded as definite HF cases, or alternatively the cases should be validated individually.
authors.affiliation: Department of Public Health and Caring Sciences, Section of Geriatrics, Uppsala University, Box 609, SE-75125 Uppsala, Sweden. erik.ingelsson@pubcare.uu.se
authors.forename: Erik
authors.initials: E
authors.lastname: Ingelsson
authors.forename: Johan
authors.initials: J
authors.lastname: Arnlöv
authors.forename: Johan
authors.initials: J
authors.lastname: Sundström
authors.forename: Lars
authors.initials: L
authors.lastname: Lind
mesh_terms: D005568:Forms and Records Control; D006333:Heart Failure / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D013548:Sweden; D014463:Ultrasonography