{
  "abstract": "Background Concussion is an acute injury that may contribute to short-term limitations and potential long-term risks.Objective To test whether a past concussion is associated with the risk of a subsequent serious motor vehicle crash.Design Population-based longitudinal cohort analysis.Setting Ontario, Canada, from 1 April 2002 to 31 March 2022 (178 emergency departments).Patients Adults diagnosed with a concussion (cases) or an acute ankle sprain (controls), excluding individuals with a disqualifying illness (blindness, dementia, delirium), severe cases resulting in hospitalisation or those who died within 90 days.Primary measure Subsequent motor vehicle crash requiring emergency medical care.Results We identified 3 037 028 patients, including 425 158 with a concussion and 2 611 870 with an ankle sprain. A total of 200 603 patients were injured in a subsequent motor vehicle crash over a median follow-up of 10 years, equal to an absolute risk of 1 in 15 patients (6.64 per 1000 patient-years). Patients with a concussion had a 49% higher motor vehicle crash risk compared with those with ankle sprain (adjusted relative risk=1.49, 95% CI 1.47 to 1.50, p<0.001). The increased risk was particularly high in the early weeks after a concussion, remained independent of other observed risk factors, applied to diverse clinical groups and was further accentuated after repeated concussions. The risk extended across a spectrum of crash severity, was accentuated for single-vehicle events, replicated in analyses with artificial intelligence methods adjusting for confounding and remained distinct from the risks of other unrelated medical emergencies.Conclusions This study suggests a significant increased risk of a motor vehicle crash after a concussion that may justify a safety warning from clinicians.",
  "authors": [
    {
      "affiliations": [
        "Sunnybrook Research Institute, Toronto, Ontario, Canada",
        "Institute for Clinical Evaluative Sciences (ICES), Toronto, Ontario, Canada",
        "Department of Medicine, University of Toronto, Toronto, Ontario, Canada",
        "Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada"
      ],
      "name": "Donald A Redelmeier"
    },
    {
      "affiliations": [
        "University of Toronto, Toronto, Ontario, Canada"
      ],
      "name": "Vidhi Bhatt"
    },
    {
      "affiliations": [
        "Department of Statistics, Stanford University, Stanford, California, USA",
        "Department of Biomedical Data Science, Stanford University, Stanford, California, USA"
      ],
      "name": "Robert Tibshirani"
    },
    {
      "affiliations": [
        "Institute for Clinical Evaluative Sciences (ICES), Toronto, Ontario, Canada"
      ],
      "name": "Samantha S M Drover"
    }
  ],
  "title": "Concussions and risk of a subsequent traffic crash: retrospective cohort analysis in Ontario, Canada",
  "uid": "7f78c481-013f-5073-9a86-8387123f092f"
}