title: Sensitivity of Medicare claims data for measuring use of standard multiagent chemotherapy regimens.
abstract: OBJECTIVE
  We sought to determine the accuracy with which Medicare billing data documents elderly Medicare cancer patients' receipt of common multiagent chemotherapy regimens.
  
  
  METHODS
  We merged gold-standard clinical trial data from 406 elderly cancer patients known to be treated on 1 of 6 Cancer and Leukemia Group B (CALGB) breast, colorectal, and lung cancer trials (trial numbers; 9344, 9730, 9235,9732, 80203, 89803) with their Medicare claims data from Centers for Medicare and Medicaid Services (CMS). Comparing CMS chemotherapy codes to gold-standard CALGB treatment data, we estimated Medicare data's sensitivity at measuring the correct drugs and schedule for each of the multiagent chemotherapy regimens.
  
  
  RESULTS
  Overall 92% (375/406) of CALGB patients had contemporaneous CMS claims indicating receipt of chemotherapy. The overall sensitivity of CMS ambulatory claims for documenting treatment with the correct drugs and on the correct schedule (ie, all drugs had to be billed on the same day) for the 5 common multiagent chemotherapy regimens was 78% (275/354) for those potentially treated in the ambulatory setting. The sensitivity was similar for all treatment regimens: carboplatin and paclitaxel 83%, 5-fluorouracil and leucovorin 80%, fluorouracil, leucovorin, and irinotecan (FOLFIRI) 76%, doxorubicin and cyclophosphamide 75%, and cisplatin and etoposide 75%.
  
  
  CONCLUSIONS
  We correctly identified at least 3-quarters of elderly Medicare cancer patients treated on a clinical trial with standard first-line multiagent chemotherapy regimens in the ambulatory setting by applying coding algorithms to their CMS claims. The algorithms may be useful in identifying cohorts of elderly Medicare patients for observational studies of the comparative effectiveness of standard multiagent chemotherapy regimens.
authors.affiliation: *Departments of Medicine and Health Care Policy, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA †Department of Biostatistics Duke University, Durham, NC.
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Lamont
authors.forename: Lan
authors.initials: L
authors.lastname: Lan
mesh_terms: D000368:Aged; D000465:Algorithms; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage* / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D004363:Drug Utilization / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007345:Insurance Claim Review / Q000706:statistics & numerical data*; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data*; D009369:Neoplasms / Q000188:drug therapy*; D015203:Reproducibility of Results; D014481:United States