CORRESPONDENCE

RESPONSE: Let's Leave the Date Out of the Name of the Standard Population

Robert N. Anderson, Mary Anne Freedman, Harry M. Rosenberg, Edward J. Sondik

Affiliation of authors: National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD.

Correspondence to: Edward J. Sondik, Ph.D., Health and Human Services, National Center for Health Statistics, Centers for Disease Control and Prevention, 6525 Belcrest Rd., Rm. 1140, Hyattsville, MD 20782.

The letter by Taylor and Anton-Culver makes some useful points about the recently implemented policy of the U.S. Department of Health and Human Services to adopt a single population standard for calculating age-adjusted death rates. Use of a single population standard will greatly reduce the burden on state and local health agencies, who heretofore often had to produce multiple death rates to match Federal benchmarks; thus, the National Cancer Institute used the 1970 population standard for producing cancer incidence and mortality data, while the National Center for Health Statistics and state vital statistics offices used the 1940 population, and other parts of the Centers for Disease Control used 1980 and 1990 (1). Not only did multiple standards create an unnecessary and enormous burden, but they created confusion among data users and the media. These problems alone justify the policy to change standards. We also agree with the authors that age-adjusted death rates have no intrinsic meaning; they are statistical constructs that permit comparisons over time and among groups, unbiased by differences in the age distributions of the compared groups. And their point that age-adjusted death rates should be supplemented by age-specific analyses is a good one that we have stressed (2).

The authors' demonstration that the new standard affects cancer incidence rates for Orange County parallels the analysis published by the National Center for Health Statistics showing the impact of the new standard on a range of causes of death not limited to the cancers (2). Since the relative weights of the new standard differ from that of the old standard, such changes are expected. In most cases, rates will increase. One of the advantages of the new standard is that it brings age-adjusted rates into closer alignment with unadjusted rates, which are better indicators of underlying risk of disease and death. One could say that age-adjusted death rates, if viewed—incorrectly—as proxies for risk, tended to understate risk. However, as the authors point out, age-adjusted rates are not measures of absolute risk, only of relative risk in comparative situations.

The calendar year reference for naming the new standard was carefully considered by the workshop that recommended the change. Reference to the year 2000 helps distinguish the standard from the previously used standards of 1940, 1970, 1980, and 1990. However, the name of the standard is typically not prominent; it is usually included only in footnotes and technical notes.

To promote understanding, the new standard will be applied retrospectively in Federal publications, so data users will have continuous time series. Therefore, data for the current and earlier years will all be in terms of the new standard, so there should be minimal reasons to consult earlier publications. As the authors point out, efforts are under way to prepare the media for the change in population standard and to emphasize the strengths and limitations of age-adjusted rates.

With respect to the future, Federal agencies and other key stakeholders who participated in the workshops that developed the recommendations have been asked to revisit the population standard in at most 10 years from the time—1997—of the workshop in which the recommendations on the population standard were developed. That would be by 2007. Experience with the new standard—favorable or unfavorable—will no doubt have a bearing on whether to retain the year 2000 as the standard or whether to change it.

REFERENCES

1 Anderson RN, Rosenberg HM. Report of the second workshop on age adjustment. Vital and Health Statistics. Vol. 4, No. 30. Hyattsville (MD): National Center for Health Statistics. December 1998.

2 Anderson RN, Rosenberg HM. Age standardization of death rates: implementation of the Year 2000 standard. National Vital Statistics Reports. Vol. 47, No. 3. Hyattsville (MD): National Center for Health Statistics. October 1998.


This article has been cited by other articles in HighWire Press-hosted journals:


             
Copyright © 2000 Oxford University Press (unless otherwise stated)
Oxford University Press Privacy Policy and Legal Statement