Table 2 Selection criteria for the University Health Network Whiplash Intervention Trial [17].

18 years of age or older.

Reside or work in the Greater Toronto Area, Mississauga, Burlington, Cambridge, Kitchener, Ajax, Pickering, or the Durham region in the province of Ontario, Canada.

Make an insurance claim for physical injury to Aviva Canada* between February 1, 2008 to March 31, 2012 within 21 days of the traffic collision.

Report an average neck pain since the accident of at least 3 on a 0-10 numerical rating scale.

Are injured in a motor vehicle collision with clinician-assessed Grade I or II WAD.

Are able to provide written informed consent and complete interviews in English (translators will be available to assist the participant if the claimant experiences difficulty understanding specific items on the questionnaire).

Exclusion criteria

Fracture/dislocation of the spine or any major bone.

Head trauma associated with loss of consciousness.

Past whiplash or work-related neck injury within the year prior to current WAD injury.

Active systemic diseases (cancer, inflammatory arthritis, disorders of central nervous system).

Previous neck surgery.

Received treatment from a physiotherapist or chiropractor for neck pain in the three months preceding the motor vehicle collision.

Does not reside or work in Greater Toronto Area, Mississauga, Burlington, Cambridge, Kitchener, Ajax, Pickering, or the Durham region in the province of Ontario, Canada.