1. Department of Biostatistics, University of Aarhus, 6 Vennelyst
Boulevard, DK-8000 Århus C, Denmark;
2. Department of Computer Science, School of Dentistry, University of
Aarhus, Denmark;
3. Department of Orthodontics, School of Dentistry, University of
Copenhagen, Denmark; and
4. Department of Community Oral Health and Pediatric Dentistry, School
of Dentistry, University of Aarhus, Denmark;