1. Epidemiology Laboratory at the Nemours Center for Childhood Cancer Research, Wilmington, Delaware
2. University of Delaware, College of Health Sciences, Newark, Delaware
3. AIDS-Malignancy Division at the University of Houston, Institute of Community Health, Houston, Texas.
4. Biostatistics & Community Health at the School of Public Health, The University of Texas Health Sciences Center, Houston, Texas
5. Divisions of Epidemiology and Disease Control, School of Public Health, The University of Texas Health Sciences Center, Houston, Texas
6. Department of Investigational Cancer Therapeutics at The University of Texas M. D. Anderson Cancer Center, Houston, Texas