Participants and procedure
Coma, traumatic brain injury
COMA
The present study followed up participants from the OCTOPUS-study, a randomized controlled trial (RCT) comparing two management strategies for mild traumatic brain injury (mTBI)- inhospital observation or a CT examination and discharge (if normal examination findings) from the hospital [From the OCTOPUS-study, information on the Personal Identification Number (PIN) including birthdate, date of inclusion/possible exposure to ionizing radiation, randomization allocation, exposure to ionizing radiation status, sex of participants, and Glasgow Coma Scale Extended (GOSE) score at 3 months after injury date was retrieved. With the PIN, radiation exposure doses could be retrieved or reconstructed through information in PACS at the Karolinska University Hospital. With the PIN, Statistics Sweden (SCB) linked the study subjects’ data with the final grade from the final year of compulsory school and eligibility for high school up to the year 2011 through The Swedish Register of Compulsory School, Leaving Certificate, 1988–2012 [