Li-Li JIANG, female, born in 1975, MD, MPH, research focuses on health statistics and epidcmiology. Correspondence should be addressed to Hal-Dong KAN. His current address is: Epidemiology Branch, National Institute of Environmental Health Sciences, P.O. Box 12233, Mail Drop A3-05, Research Triangle Park, NC 27709, U. S. E-mail: haldongkan@gmall.com