Sports-related brain injury research: methodological difficulties associated with ambiguous terminology.

A basic premise underlying sound methodological research is that it is based on constructs that have a sound operational definition. Failure to do so impedes comparison with other relevant literature. In sports-related brain injury research, the varied criteria and inconsistent use of the term 'concussion' and its interchangeability with other generic terms such as mild/minor head injury, and mild brain injury exemplifies such a situation. This paper will background the issues involved and provide rationale to support a call for tightening the use of terminology in the area.