1. Division of Biometrics I, Office of Biostatistics; Office of Translational Sciences, Center of Drug Evaluation and Research (CDER), US Food and Drug Administration; Silver Spring MD U.S.A.
2. Department of Statistics and Actuarial Science; The University of Iowa; Iowa City IA U.S.A.
3. Pediatrics Epidemiology Center; University of South Florida; Tampa FL U.S.A.
4. CSR Incorporated; Arlington VA U.S.A.