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Journal of Epidemiology and Community Health logoLink to Journal of Epidemiology and Community Health
. 2001 Dec;55(12):885–890. doi: 10.1136/jech.55.12.885

Interval estimation of the attributable risk in case-control studies with matched pairs

K Lui
PMCID: PMC1731820  PMID: 11707482

Abstract

OBJECTIVE—The attributable risk (AR), which represents the proportion of cases who can be preventable when we completely eliminate a risk factor in a population, is the most commonly used epidemiological index to assess the impact of controlling a selected risk factor on community health. The goal of this paper is to develop and search for good interval estimators of the AR for case-control studies with matched pairs.
METHODS—This paper considers five asymptotic interval estimators of the AR, including the interval estimator using Wald's statistic suggested elsewhere, the two interval estimators using the logarithmic transformations: log(x) and log(1-x), the interval estimator using the logit transformation log(x/(1-x)), and the interval estimator derived from a simple quadratic equation developed in this paper. This paper compares the finite sample performance of these five interval estimators by calculation of their coverage probability and average length in a variety of situations.
RESULTS—This paper demonstrates that the interval estimator derived from the quadratic equation proposed here can not only consistently perform well with respect to the coverage probability, but also be more efficient than the interval estimator using Wald's statistic in almost all the situations considered here. This paper notes that although the interval estimator using the logarithmic transformation log(1-x) may also perform well with respect to the coverage probability, using this estimator is likely to be less efficient than the interval estimator using Wald's statistic. Finally, this paper notes that when both the underlying odds ratio (OR) and the prevalence of exposure (PE) in the case group are not large (OR ⩽2 and PE ⩽0.10), the application of the two interval estimators using the transformations log(x) and log(x/(1-x)) can be misleading. However, when both the underlying OR and PE in the case group are large (OR ⩾4 and PE ⩾0.50), the interval estimator using the logit transformation can actually outperform all the other estimators considered here in terms of efficiency.
CONCLUSIONS—When there is no prior knowledge of the possible range for the underlying OR and PE, the interval estimator derived from the quadratic equation developed here for general use is recommended. When it is known that both the OR and PE in the case group are large (OR ⩾4 and PE ⩾0.50), it is recommended that the interval estimator using the logit transformation is used.


Keywords: case-control studies; attributable risk; interval estimation

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Selected References

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  1. Antunes C. M., Strolley P. D., Rosenshein N. B., Davies J. L., Tonascia J. A., Brown C., Burnett L., Rutledge A., Pokempner M., Garcia R. Endometrial cancer and estrogen use. Report of a large case-control study. N Engl J Med. 1979 Jan 4;300(1):9–13. doi: 10.1056/NEJM197901043000103. [DOI] [PubMed] [Google Scholar]
  2. Benichou J. Methods of adjustment for estimating the attributable risk in case-control studies: a review. Stat Med. 1991 Nov;10(11):1753–1773. doi: 10.1002/sim.4780101113. [DOI] [PubMed] [Google Scholar]
  3. Bruzzi P., Green S. B., Byar D. P., Brinton L. A., Schairer C. Estimating the population attributable risk for multiple risk factors using case-control data. Am J Epidemiol. 1985 Nov;122(5):904–914. doi: 10.1093/oxfordjournals.aje.a114174. [DOI] [PubMed] [Google Scholar]
  4. Denman D. W., 3rd, Schlesselman J. J. Interval estimation of the attributable risk for multiple exposure levels in case-control studies. Biometrics. 1983 Mar;39(1):185–192. [PubMed] [Google Scholar]
  5. Drescher K., Schill W. Attributable risk estimation from case-control data via logistic regression. Biometrics. 1991 Dec;47(4):1247–1256. [PubMed] [Google Scholar]
  6. Fleiss J. L. Inference about population attributable risk from cross-sectional studies. Am J Epidemiol. 1979 Aug;110(2):103–104. doi: 10.1093/oxfordjournals.aje.a112794. [DOI] [PubMed] [Google Scholar]
  7. Gefeller O., Windeler J. Risk factors for cervical cancer: comments on attributable risk calculations and the evaluation of screening in case-control studies. Int J Epidemiol. 1991 Dec;20(4):1140–1143. doi: 10.1093/ije/20.4.1140. [DOI] [PubMed] [Google Scholar]
  8. Greenland S., Drescher K. Maximum likelihood estimation of the attributable fraction from logistic models. Biometrics. 1993 Sep;49(3):865–872. [PubMed] [Google Scholar]
  9. Kooperberg C., Petitti D. B. Using logistic regression to estimate the adjusted attributable risk of low birthweight in an unmatched case-control study. Epidemiology. 1991 Sep;2(5):363–366. doi: 10.1097/00001648-199109000-00009. [DOI] [PubMed] [Google Scholar]
  10. Kuritz S. J., Landis J. R. Attributable risk estimation from matched case-control data. Biometrics. 1988 Jun;44(2):355–367. [PubMed] [Google Scholar]
  11. Kuritz S. J., Landis J. R. Attributable risk ratio estimation from matched-pairs case-control data. Am J Epidemiol. 1987 Feb;125(2):324–328. doi: 10.1093/oxfordjournals.aje.a114533. [DOI] [PubMed] [Google Scholar]
  12. Kuritz S. J., Landis J. R. Summary attributable risk estimation from unmatched case-control data. Stat Med. 1988 Apr;7(4):507–517. doi: 10.1002/sim.4780070407. [DOI] [PubMed] [Google Scholar]
  13. LEVIN M. L. The occurrence of lung cancer in man. Acta Unio Int Contra Cancrum. 1953;9(3):531–541. [PubMed] [Google Scholar]
  14. Leung H. M., Kupper L. L. Comparisons of confidence intervals for attributable risk. Biometrics. 1981 Jun;37(2):293–302. [PubMed] [Google Scholar]
  15. Miettinen O. S. Proportion of disease caused or prevented by a given exposure, trait or intervention. Am J Epidemiol. 1974 May;99(5):325–332. doi: 10.1093/oxfordjournals.aje.a121617. [DOI] [PubMed] [Google Scholar]
  16. Taylor J. W. Simple estimation of population attributable risk from case-control studies. Am J Epidemiol. 1977 Oct;106(4):260–260. doi: 10.1093/oxfordjournals.aje.a112461. [DOI] [PubMed] [Google Scholar]
  17. Walter S. D. The estimation and interpretation of attributable risk in health research. Biometrics. 1976 Dec;32(4):829–849. [PubMed] [Google Scholar]
  18. Whittemore A. S. Estimating attributable risk from case-control studies. Am J Epidemiol. 1983 Jan;117(1):76–85. doi: 10.1093/oxfordjournals.aje.a113518. [DOI] [PubMed] [Google Scholar]
  19. Whittemore A. S. Statistical methods for estimating attributable risk from retrospective data. Stat Med. 1982 Jul-Sep;1(3):229–243. doi: 10.1002/sim.4780010305. [DOI] [PubMed] [Google Scholar]

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