This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Hujoel, P.P. Articles by Makinen, K.K. Search for Related Content PubMed PubMed Citation Articles by Hujoel, P.P. Articles by Makinen, K.K. Social Bookmarking                         What's this?

A Re-analysis of Caries Rates in a Preventive Trial using Poisson Regression Models

Department of Dental Public Health Sciences, School of Dentistry, SM-35, University of Washington, Seattle, Washington 98195, Department of Epidemiology, School of Public Health and Community Medicine

P.J. Isokangas

Department of Community Dentistry, Institute of Dentistry, University of Turku, Finland

J. Tiekso

Department of Community Dentistry, Institute of Dentistry, University of Turku, Finland

S. Davis

Department of Epidemiology, School of Public Health and Community Medicine, Fred Hutchinson Cancer Research Center, Division of Public Health Sciences, Program in Epidemiology, and University of Washington, Seattle

R.J. Lamont

Department of Oral Biology, University of Washington, Seattle

T.A. DeRouen

Department of Dental Public Health Sciences, School of Dentistry, SM-35, University of Washington, Seattle, Washington 98195, Department of Biostatistics, University of Washington, Seattle

K.K. Makinen

Department of Biological and Material Sciences, University of Michigan, Ann Arbor, Michigan 48109

The analysis of caries incidence in clinical trials has several challenging features: (1) The distribution of the number of caries onsets per patient is skewed, with the majority of patients having few or no cavities; (2) the number of surfaces at risk varies (i) over time and (ii) between patients, due to eruption and exfoliation patterns, dental diseases, and treatments ; (3) surfaces within a patient differ in their caries susceptibility, and (4) caries onsets within a patient are correlated due to shared host factors. Recent statistical developments in the area of correlated data analyses permit incorporation of some of these characteristics into the analyses. With Poisson regression models, the expected number of caries onsets can be related to the number of surfaces at risk, the time they have been at risk, and surface- and subject-specific explanatory variables. The parameter estimated in these models is an epidemiological measure of disease occurrence: the disease incidence rate (caries rate) or the rate of change from healthy (sound) to diseased (carious). Differences and ratios of these rates provide standard epidemiological measures of excess risk. To illustrate, Poisson regression models were used for exploratory analyses of the Ylivieska xylitol study.

Key Words: Dental Caries • Models • Statistical, Xylitol

Journal of Dental Research, Vol. 73, No. 2, 573-579 (1994)
DOI: 10.1177/00220345940730021401


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				J.W. Stamm The Classic Caries Clinical Trial: Constraints and Opportunities Journal of Dental Research, July 1, 2004; 83(suppl_1): C6 - C14. [Full Text] [PDF]

				L.A. Mancl, P.P. Hujoel, and T.A. DeRouen Efficiency Issues Among Statistical Methods for Demonstrating Efficacy of Caries Prevention Journal of Dental Research, July 1, 2004; 83(suppl_1): C95 - C98. [Abstract] [Full Text] [PDF]

				B.P. Katz and E. Huntington Statistical Issues for Combining Multiple Caries Diagnostics for Demonstrating Caries Efficacy Journal of Dental Research, July 1, 2004; 83(suppl_1): C109 - C112. [Abstract] [Full Text] [PDF]

				M.F. Johnson The Role of Risk Factors in the Identification of Appropriate Subjects for Caries Clinical Trials: Design Considerations Journal of Dental Research, July 1, 2004; 83(suppl_1): C116 - C118. [Abstract] [Full Text] [PDF]

				R. C. PAGE, E. A. KRALL, J. MARTIN, L. MANCL, and R. I. GARCIA Validity and accuracy of a risk calculator in predicting periodontal disease J Am Dent Assoc, May 1, 2002; 133(5): 569 - 576. [Abstract] [Full Text] [PDF]

				P.P. Hujoel, K.K. Makinen, C.A. Bennett, K.P. Isotupa, P.J. Isokangas, P. Allen, and P.-L. Makinen The Optimum Time to Initiate Habitual Xylitol Gum-chewing for Obtaining Long-term Caries Prevention Journal of Dental Research, March 1, 1999; 78(3): 797 - 803. [Abstract] [PDF]

				P.P. Hujoel, H. Loe, A. Anerud, H. Boysen, and B.G. Leroux Forty-five-year Tooth Survival Probabilities among Men in Oslo, Norway Journal of Dental Research, December 1, 1998; 77(12): 2020 - 2027. [Abstract] [PDF]