Average injury rates weighted by sample size are 16.3/1000AE for 8/11 competition studies and 69.5/1000AE for 5/27 databases. Competition data are likely to be accurate because they were observed by physicians, trainers and referees and the completeness and accuracy of database studies vary. Databases which extrapolated data to provide annual national rates estimated large numbers. Few studies provided data about the situations in which injuries occur and the causes of injuries.