title: The challenge of mapping between two medical coding systems.
abstract: OBJECTIVE
  Deployable medical systems patient conditions (PCs) designate groups of patients with similar medical conditions and, therefore, similar treatment requirements. PCs are used by the U.S. military to estimate field medical resources needed in combat operations. Information associated with each of the 389 PCs is based on subject matter expert opinion, instead of direct derivation from standard medical codes. Currently, no mechanisms exist to tie current or historical medical data to PCs. Our study objective was to determine whether reliable conversion between PC codes and International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) diagnosis codes is possible.
  
  
  METHODS
  Data were analyzed for three professional coders assigning all applicable ICD-9-CM diagnosis codes to each PC code. Inter-rater reliability was measured by using Cohen's K statistic and percent agreement. Methods were developed to calculate kappa statistics when multiple responses could be selected from many possible categories.
  
  
  RESULTS
  Overall, we found moderate support for the possibility of reliable conversion between PCs and ICD-9-CM diagnoses (mean kappa = 0.61).
  
  
  CONCLUSIONS
  Current PCs should be modified into a system that is verifiable with real data.
authors.affiliation: Center for Army Medical Department Strategic Studies, U.S. Army Medical Department Center and School, Fort Sam Houston, TX 78234-5047, USA.
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Wojcik
authors.forename: Catherine R
authors.initials: CR
authors.lastname: Stein
authors.forename: Raymond B
authors.initials: RB
authors.lastname: Devore
authors.forename: L Harrison
authors.initials: LH
authors.lastname: Hassell
mesh_terms: D003953:Diagnosis-Related Groups; D005568:Forms and Records Control / Q000379:methods*; D006801:Humans; D038801:International Classification of Diseases; D008497:Medical Record Administrators; D008499:Medical Records / Q000145:classification*; D008887:Military Medicine / Q000145:classification*; D008889:Military Personnel; D015588:Observer Variation; D009784:Occupational Diseases / Q000145:classification*; D015203:Reproducibility of Results; D014218:Triage / Q000145:classification*; D014481:United States; D014857:Warfare; D014947:Wounds and Injuries / Q000145:classification*