title: Hospital discharge diagnoses of ventricular arrhythmias and cardiac arrest were useful for epidemiologic research.
abstract: OBJECTIVE
  We investigated the validity of hospital discharge diagnosis regarding ventricular arrhythmias and cardiac arrest.
  
  
  METHODS
  We identified patients whose record in the PHARMO record linkage system database showed a code for ventricular or unspecified cardiac arrhythmias according to codes of the International Classification of Diseases, 9th revision, clinical modification (ICD-9-CM). The validity of ICD codes for ventricular arrhythmias and cardiac arrest (427.1, 427.4, 427.41, 427.42, 427.5, 427.69) and ICD codes for unspecified cardiac arrhythmias (427.2, 427.60, 427.8, 427.89, 427.9) was ascertained through manual review of hospital clinical records. The positive predictive value (PPV) was calculated, and differences between characteristics of true and false positives were evaluated.
  
  
  RESULTS
  The PPV of ICD codes for ventricular arrhythmias and cardiac arrest was 82% (95% confidence interval CI = 72-92). True positive results were associated with male gender (P = .09) and younger age (P = .05). Of the unspecified cardiac arrhythmias 10% (95% CI = 2-18) were identified as ventricular arrhythmias or cardiac arrest.
  
  
  CONCLUSIONS
  Hospitalizations for ventricular cardiac arrhythmias and cardiac arrest (coded according to ICD-9-CM as paroxysmal ventricular tachycardia, ventricular fibrillation, ventricular flutter, ventricular premature beats, or cardiac arrest) have a high PPV and are useful for selecting events in epidemiological studies on drug-induced arrhythmias.
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences (UIPS), Department of Pharmacoepidemiology and Pharmacotherapy, Utrecht University, The Netherlands. m.l.debruin@pharm.uu.nl
authors.forename: M L
authors.initials: ML
authors.lastname: De Bruin
authors.forename: N M
authors.initials: NM
authors.lastname: van Hemel
authors.forename: H G M
authors.initials: HG
authors.lastname: Leufkens
authors.forename: A W
authors.initials: AW
authors.lastname: Hoes
mesh_terms: D003625:Data Collection; D004812:Epidemiologic Methods; D015340:Epidemiologic Research Design; D005260:Female; D006323:Heart Arrest / Q000175:diagnosis*; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D008499:Medical Records; D010351:Patient Discharge; D017180:Tachycardia, Ventricular / Q000175:diagnosis*; D014693:Ventricular Fibrillation / Q000175:diagnosis*