TY - JOUR
T1 - A reproducibility study for a fluoride assay in bone
AU - Medina, Nancy
AU - Douglass, Chester W.
AU - Whitford, Gary M.
AU - Hoover, Robert N.
AU - Fears, Thomas R.
PY - 2006/5
Y1 - 2006/5
N2 - Osteosarcoma is a rare malignancy of largely unknown etiology. Although there is no consistent evidence for an association between fluoridation and cancer, some concerns remain about osteosarcoma. As part of the design of a collaborative study, bone samples were collected to allow for an evaluation of the association between osteosarcoma risk and individual fluoride exposure measured by levels of fluoride in bone. In this report, we provide the results of pilot experiments to consider issues that arose during the study design and to assess the reliability of the bone assays. Correlations of fluoride levels between normal bone near the affected area and iliac crest bone were strong and positive. The day-to-day laboratory analysis of fluoride in human and deer jaw bone yielded acceptable average coefficients of variation below 10% and an overall estimate of 5%. The intraclass correlation (ICC) is of particular importance to epidemiologists because it indicates the effect of measurement error on study results. Here, the estimated ICC is 0.86, and the estimated downward bias is only 14%. Hence, the ICC is strong enough so that the estimates of the relative risk will suffer little attenuation from lab measurements.
AB - Osteosarcoma is a rare malignancy of largely unknown etiology. Although there is no consistent evidence for an association between fluoridation and cancer, some concerns remain about osteosarcoma. As part of the design of a collaborative study, bone samples were collected to allow for an evaluation of the association between osteosarcoma risk and individual fluoride exposure measured by levels of fluoride in bone. In this report, we provide the results of pilot experiments to consider issues that arose during the study design and to assess the reliability of the bone assays. Correlations of fluoride levels between normal bone near the affected area and iliac crest bone were strong and positive. The day-to-day laboratory analysis of fluoride in human and deer jaw bone yielded acceptable average coefficients of variation below 10% and an overall estimate of 5%. The intraclass correlation (ICC) is of particular importance to epidemiologists because it indicates the effect of measurement error on study results. Here, the estimated ICC is 0.86, and the estimated downward bias is only 14%. Hence, the ICC is strong enough so that the estimates of the relative risk will suffer little attenuation from lab measurements.
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U2 - 10.1158/1055-9965.EPI-05-0796
DO - 10.1158/1055-9965.EPI-05-0796
M3 - Article
C2 - 16702389
AN - SCOPUS:33744719106
SN - 1055-9965
VL - 15
SP - 1035
EP - 1037
JO - Cancer Epidemiology Biomarkers and Prevention
JF - Cancer Epidemiology Biomarkers and Prevention
IS - 5
ER -