Skip to main content
NCBI home page
American Journal of Public Health logoLink to American Journal of Public Health
. 1992 Feb;82(2):243–248. doi: 10.2105/ajph.82.2.243

The accuracy of Medicare's hospital claims data: progress has been made, but problems remain.

E S Fisher 1, F S Whaley 1, W M Krushat 1, D J Malenka 1, C Fleming 1, J A Baron 1, D C Hsia 1
PMCID: PMC1694279  PMID: 1739155

Abstract

BACKGROUND. Health care databases provide a widely used source of data for health care research, but their accuracy remains uncertain. We analyzed data from the 1985 National DRG Validation Study, which carefully reabstracted and reassigned ICD-9-CM diagnosis and procedure codes from a national sample of 7050 medical records, to determine whether coding accuracy had improved since the Institute of Medicine studies of the 1970s and to assess the current coding accuracy of specific diagnoses and procedures. METHODS. We defined agreement as the proportion of all reabstracted records that had the same principal diagnosis or procedure coded on both the original (hospital) record and on the reabstracted record. We also evaluated coding accuracy in 1985 using the concepts of diagnostic test evaluation. RESULTS. Overall, the percentage of agreement between the principal diagnosis on the reabstracted record and the original hospital record, when analyzed at the third digit, improved from 73.2% in 1977 to 78.2% in 1985. However, analysis of the 1985 data demonstrated that the accuracy of diagnosis and procedure coding varies substantially across conditions. CONCLUSIONS. Although some diagnoses and all major surgical procedures that we examined were accurately coded, the variability in the accuracy of diagnosis coding poses a problem that must be overcome if claims-based research is to achieve its full potential.

Full text

PDF
243

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Cohen B. B., Pokras R., Meads M. S., Krushat W. M. How will diagnosis-related groups affect epidemiologic research? Am J Epidemiol. 1987 Jul;126(1):1–9. doi: 10.1093/oxfordjournals.aje.a114639. [DOI] [PubMed] [Google Scholar]
  2. Demlo L. K., Campbell P. M. Improving hospital discharge data: lessons from the National Hospital Discharge Survey. Med Care. 1981 Oct;19(10):1030–1040. doi: 10.1097/00005650-198110000-00005. [DOI] [PubMed] [Google Scholar]
  3. Dubois R. W., Brook R. H., Rogers W. H. Adjusted hospital death rates: a potential screen for quality of medical care. Am J Public Health. 1987 Sep;77(9):1162–1166. doi: 10.2105/ajph.77.9.1162. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Dubois R. W., Rogers W. H., Moxley J. H., 3rd, Draper D., Brook R. H. Hospital inpatient mortality. Is it a predictor of quality? N Engl J Med. 1987 Dec 24;317(26):1674–1680. doi: 10.1056/NEJM198712243172626. [DOI] [PubMed] [Google Scholar]
  5. Farmer M. E., White L. R., Brody J. A., Bailey K. R. Race and sex differences in hip fracture incidence. Am J Public Health. 1984 Dec;74(12):1374–1380. doi: 10.2105/ajph.74.12.1374. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Fisher E. S., Baron J. A., Malenka D. J., Barrett J. A., Kniffin W. D., Whaley F. S., Bubolz T. A. Hip fracture incidence and mortality in New England. Epidemiology. 1991 Mar;2(2):116–122. doi: 10.1097/00001648-199103000-00005. [DOI] [PubMed] [Google Scholar]
  7. Fisher E. S. Helping patients choose treatments. An important role for administrative health care databases. Chest. 1991 Sep;100(3):595–596. doi: 10.1378/chest.100.3.595. [DOI] [PubMed] [Google Scholar]
  8. Fisher E. S., Malenka D. J., Solomon N. A., Bubolz T. A., Whaley F. S., Wennberg J. E. Risk of carotid endarterectomy in the elderly. Am J Public Health. 1989 Dec;79(12):1617–1620. doi: 10.2105/ajph.79.12.1617. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Greenfield S., Aronow H. U., Elashoff R. M., Watanabe D. Flaws in mortality data. The hazards of ignoring comorbid disease. JAMA. 1988 Oct 21;260(15):2253–2255. [PubMed] [Google Scholar]
  10. Hsia D. C., Krushat W. M., Fagan A. B., Tebbutt J. A., Kusserow R. P. Accuracy of diagnostic coding for Medicare patients under the prospective-payment system. N Engl J Med. 1988 Feb 11;318(6):352–355. doi: 10.1056/NEJM198802113180604. [DOI] [PubMed] [Google Scholar]
  11. Iezzoni L. I., Burnside S., Sickles L., Moskowitz M. A., Sawitz E., Levine P. A. Coding of acute myocardial infarction. Clinical and policy implications. Ann Intern Med. 1988 Nov 1;109(9):745–751. doi: 10.7326/0003-4819-109-9-745. [DOI] [PubMed] [Google Scholar]
  12. Iezzoni L. I., Moskowitz M. A. Clinical overlap among medical diagnosis-related groups. JAMA. 1986 Feb 21;255(7):927–929. [PubMed] [Google Scholar]
  13. Jencks S. F., Williams D. K., Kay T. L. Assessing hospital-associated deaths from discharge data. The role of length of stay and comorbidities. JAMA. 1988 Oct 21;260(15):2240–2246. [PubMed] [Google Scholar]
  14. Kellie S. E., Brody J. A. Sex-specific and race-specific hip fracture rates. Am J Public Health. 1990 Mar;80(3):326–328. doi: 10.2105/ajph.80.3.326. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Lloyd S. S., Rissing J. P. Physician and coding errors in patient records. JAMA. 1985 Sep 13;254(10):1330–1336. [PubMed] [Google Scholar]
  16. Maerki S. C., Luft H. S., Hunt S. S. Selecting categories of patients for regionalization. Implications of the relationship between volume and outcome. Med Care. 1986 Feb;24(2):148–158. doi: 10.1097/00005650-198602000-00006. [DOI] [PubMed] [Google Scholar]
  17. McPherson K., Wennberg J. E., Hovind O. B., Clifford P. Small-area variations in the use of common surgical procedures: an international comparison of New England, England, and Norway. N Engl J Med. 1982 Nov 18;307(21):1310–1314. doi: 10.1056/NEJM198211183072104. [DOI] [PubMed] [Google Scholar]
  18. Ray W. A., Griffin M. R., Schaffner W., Baugh D. K., Melton L. J., 3rd Psychotropic drug use and the risk of hip fracture. N Engl J Med. 1987 Feb 12;316(7):363–369. doi: 10.1056/NEJM198702123160702. [DOI] [PubMed] [Google Scholar]
  19. Roos N. P., Wennberg J. E., Malenka D. J., Fisher E. S., McPherson K., Andersen T. F., Cohen M. M., Ramsey E. Mortality and reoperation after open and transurethral resection of the prostate for benign prostatic hyperplasia. N Engl J Med. 1989 Apr 27;320(17):1120–1124. doi: 10.1056/NEJM198904273201705. [DOI] [PubMed] [Google Scholar]
  20. Roper W. L., Winkenwerder W., Hackbarth G. M., Krakauer H. Effectiveness in health care. An initiative to evaluate and improve medical practice. N Engl J Med. 1988 Nov 3;319(18):1197–1202. doi: 10.1056/NEJM198811033191805. [DOI] [PubMed] [Google Scholar]
  21. Sox H. C., Jr Probability theory in the use of diagnostic tests. An introduction to critical study of the literature. Ann Intern Med. 1986 Jan;104(1):60–66. doi: 10.7326/0003-4819-104-1-60. [DOI] [PubMed] [Google Scholar]
  22. Wennberg J. E., Roos N., Sola L., Schori A., Jaffe R. Use of claims data systems to evaluate health care outcomes. Mortality and reoperation following prostatectomy. JAMA. 1987 Feb 20;257(7):933–936. [PubMed] [Google Scholar]
  23. Wennberg J., Gittelsohn Small area variations in health care delivery. Science. 1973 Dec 14;182(4117):1102–1108. doi: 10.1126/science.182.4117.1102. [DOI] [PubMed] [Google Scholar]
  24. Whittle J., Steinberg E. P., Anderson G. F., Herbert R. Use of Medicare claims data to evaluate outcomes in elderly patients undergoing lung resection for lung cancer. Chest. 1991 Sep;100(3):729–734. doi: 10.1378/chest.100.3.729. [DOI] [PubMed] [Google Scholar]

Articles from American Journal of Public Health are provided here courtesy of American Public Health Association

RESOURCES