Nonparametric estimation of reference intervals by simple and bootstrap-based procedures.

on determinations of hemoglobin A1c by an immunoassay method. Diabetes Care 1998;21:983–6. 6. Roberts WL, Chiasera JM, Ward-Cook KM. Glycohemoglobin results in samples with hemoglobin C or S trait: a comparison of four test systems. Clin Chem 1999;45:906–9. 7. Eckman JR. The Sickle Cell Foundation of Georgia, Inc. The Sickle Cell Information Center. http://www.emory.edu/PEDS/SICKLE/hemoglb.htm (accessed May 1999). 8. National Heart, Lung, and Blood Institute. Management and therapy of sickle cell disease. Sickle cell trait. http://www.nhlbi.nih.gov/health/prof/blood/ sickle/sickle.txt (accessed August 1999). 9. Meyer LM, Adams JG III, Steinberg MH, Miller IE, Stokes N. Screening for sickle cell trait: the Veterans Administration National Sickle Cell Program. Am J Hematol 1987;24:429–32. 10. US Department of Commerce, Economics and Statistics Administration, Bureau of the Census. We the Americans: Blacks. http://www.census.gov/ apsd/wepeople/we-1.pdf (accessed February 2000). 11. Harris MI, Flegal KM, Cowie CC, Eberhardt MS, Goldstein DE, Little RR, et al. Prevalence of diabetes, impaired fasting glucose, and impaired glucose tolerance in U.S. adults. The third National Health and Nutrition Examination Survey, 1988–1994. Diabetes Care 1998:21:518–24. 12. Abraham EC. Glycosylated hemoglobins. New York: Marcel Dekker, 1985: 91–171. 13. Fluckiger R. Glycated hemoglobins [Review]. J Chromatogr 1988;429:279– 92. 14. Nuttall FQ. Comparison of percent total gHb with percent HbA1c in people with and without known diabetes. Diabetes Care 1998;21:1475–80. 15. Holownia P, Bishop E, Newman DJ, John WG, Price CP. Adaptation of latex-enhanced assay for percent glycohemoglobin to a Dade Dimension analyzer. Clin Chem 1997;43:76–84.