1. Section for Sports Science; Department of Public Health; Aarhus University; Aarhus C Denmark
2. Australian Collaboration for Research into Injury in Sport and its Prevention; Federation University Australia; Ballarat Vic. Australia
3. Department of Health Science and Technology; Aalborg University, SMI®; Aalborg Denmark
4. Section of Biostatistics; Department of Public Health; Aarhus University; Aarhus C Denmark