title: Profiling providers on use of adjuvant chemotherapy by combining cancer registry and medical record data.
abstract: OBJECTIVE
  Treatment information collected by cancer registries can be used to monitor the provision of guideline-recommended chemotherapy to colorectal cancer patients. Incomplete information may bias comparisons of these rates. We developed statistical methods that combine data from a registry and physicians' records to assess hospital quality.
  
  
  METHODS
  From California Cancer Registry data, we selected all patients (n=12,594) newly diagnosed with stage III colon cancer or stage II or III rectal cancer from 428 hospitals during the years 1994 to 1998. To assess rates and predictors of underreporting of chemotherapy, we surveyed physicians treating 1449 of these patients from 98 hospitals during the years 1996 to 1997.
  
  
  METHODS
  Using Bayesian statistical models, we imputed unobserved treatments. We studied the impact of underreporting on provider profiling by comparing rankings, estimates, and credible intervals based only on registry data to those incorporating physician survey data.
  
  
  RESULTS
  Analyses that account for incompleteness of reporting yielded wider credible intervals for provider profiles than those that ignored such incompleteness. Among the 109 (25%) hospitals in the highest quartile of chemotherapy rates according to the registry data, 16 were not so classified when incomplete reporting was taken into account. With the more comprehensive model, 12 hospitals could be identified that ranked in the top quartile with probability>0.90.
  
  
  CONCLUSIONS
  Estimates of adjusted hospital chemotherapy rates based solely on cancer registry data overstate the precision of assessments of hospital quality. Using additional information from a physician survey and applying rigorous statistical models, better inferences can be drawn about provider quality.
authors.affiliation: Department of Health Care Policy, Harvard Medical School, and Division of Epidemiology and Outcomes Research, Partners AIDS Research Center, Massachusetts General Hospital, Boston 02115, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Zheng
authors.forename: Recai
authors.initials: R
authors.lastname: Yucel
authors.forename: John Z
authors.initials: JZ
authors.lastname: Ayanian
authors.forename: Alan M
authors.initials: AM
authors.lastname: Zaslavsky
mesh_terms: D000293:Adolescent; D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001499:Bayes Theorem; D002140:California; D017024:Chemotherapy, Adjuvant / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D003625:Data Collection; D005260:Female; D019983:Guideline Adherence; D006761:Hospitals / Q000592:standards; D006801:Humans; D008297:Male; D008499:Medical Records / Q000592:standards* / Q000706:statistics & numerical data; D008875:Middle Aged; D009367:Neoplasm Staging; D011787:Quality of Health Care; D012042:Registries / Q000592:standards* / Q000706:statistics & numerical data
chemical_list: D000970:Antineoplastic Agents