1. Department of Pediatrics, Harvard Medical School, Boston, Massachusetts;
2. Division of Developmental Medicine,
3. Division of Adolescent/Young Adult Medicine, and
4. The Center for Adolescent Substance Abuse Research, Children’s Hospital Boston, Boston, Massachusetts (Coordinating Site);
5. Centre for Evaluation, Prevention and Research of Substance Abuse, Prague, Czech Republic;
6. Prague Psychiatric Centre, Prague, Czech Republic;
7. The Faculty of Humanities, Charles University, Prague, Czech Republic;
8. Institute of Behavioral Health, Heller School of Social Policy and Management, Brandeis University, Waltham, Massachusetts;
9. Concord Hospital Family Health Center, Pediatrics, Concord, New Hampshire;
10. Department of Pediatrics, Cambridge Health Alliance, Cambridge, Massachusetts;
11. Teen Health Center, Cambridge Rindge and Latin High School, Cambridge, Massachusetts;
12. Teen Health Center, Somerville High School, Somerville, Massachusetts;
13. Family Practice Associates, Cambridge Health Center, Cambridge, Vermont;
14. Department of Pediatrics, Reliant Medical Group, Inc., Worcester, Massachusetts;
15. Department of Pediatrics, Tufts Medical Center-Floating Hospital for Children, Boston, Massachusetts; and
16. Dartmouth-Hitchcock Concord, Pediatrics, Concord, New Hampshire