title: Accuracy of pharmacy and coded-diagnosis information in identifying tuberculosis in patients with rheumatoid arthritis.
abstract: OBJECTIVE
  Previous studies suggest that disease-modifying anti-rheumatic drugs (DMARDs) increase tuberculosis (TB) risk. The accuracy of pharmacy and coded-diagnosis information to identify persons with TB is unclear.
  
  
  METHODS
  Within a cohort of rheumatoid arthritis (RA) patients (2000-2005) enrolled in Tennessee Medicaid, we identified those with potential TB using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD9-CM) diagnosis codes and/or pharmacy claims. Using the Tennessee TB registry as the gold standard for identification of TB, we estimated the sensitivity, specificity, predictive values, and the respective 95% confidence intervals for each TB case-ascertainment strategy.
  
  
  RESULTS
  Ten of 18,094 RA patients had confirmed TB during 61,461 person-years of follow-up (16.3 per 100,000 person-years). The sensitivity and positive predictive value (PPV) and respective 95% confidence intervals were low for confirmed TB based on ICD9-CM codes alone (60.0% (26.2-87.8) and 1.3% (0.5-2.9)), pharmacy data alone (20% (2.5-55.6) and 4.1% (0.5-14.3)), and both (20% (2.5-55.6) and 25.0% (3.2-65.1)).
  
  
  CONCLUSIONS
  Algorithms that use administrative data alone to identify TB have a poor PPV that results in a high false positive rate of TB detection.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA.
authors.forename: Christina T
authors.initials: CT
authors.lastname: Fiske
authors.forename: Marie R
authors.initials: MR
authors.lastname: Griffin
authors.forename: Ed
authors.initials: E
authors.lastname: Mitchel
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Sterling
authors.forename: Carlos G
authors.initials: CG
authors.lastname: Grijalva
mesh_terms: D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D000995:Antitubercular Agents / Q000008:administration & dosage / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D015331:Cohort Studies; D003157:Community Pharmacy Services / Q000592:standards / Q000706:statistics & numerical data*; D017723:Drug Utilization Review; D006801:Humans; D015994:Incidence; D007345:Insurance Claim Review; D038801:International Classification of Diseases / Q000592:standards / Q000706:statistics & numerical data*; D008484:Medicaid; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013714:Tennessee / Q000453:epidemiology; D014376:Tuberculosis / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D014481:United States
chemical_list: D018501:Antirheumatic Agents; D000995:Antitubercular Agents