Material and method
The study was conducted at the Emergency Department, Oslo University Hospital, Ullevål, in the period June 2018–March 2019. The Regional Committee for Medical and Health Research Ethics classified the study as a quality assurance study, and as such it was outside their mandate. The study was approved by the Data Protection Officer at Oslo University Hospital (case number 17/1740) and registered at clinicaltrials.gov (registration number NCT 03730272).
Patients were assessed for possible inclusion in a daily review of the trauma register at Oslo University Hospital. The inclusion criteria were as follows: aged 18 and over, sent directly to our trauma team from the site where the injury was incurred, an ISS score higher than 8, competent to give consent and ability to communicate well in Norwegian or English. The Injury Severity Score (ISS) has a scale from 0 to 75, and the score is calculated by grading the severity of the injury from 1 to 6 in each of six body regions. The scores from the three most severely injured body regions are then squared and added together. An ISS score of 9 can indicate a moderate injury in two different regions or one moderate to severe injury in one region.
We excluded patients who were intubated, or had isolated head injuries, a Glasgow Coma Scale score below 9, a high spinal cord transection, a diagnosed substance abuse disorder, or were discharged within six hours.
Written informed consent was obtained, and data were collected from patient records, the trauma register and patient interviews. The interviews were conducted an average of two weeks (95 % within 11–17 days) after the injury was incurred. Patients were asked about the pain they experienced after the injury. For pain intensity, they were asked about the average pain, average resting pain and worst pain that they experienced during the two-week period, indicated by a verbal numeric rating scale (VNRS) from 0 to 10 (0 = no pain, 10 = worst pain imaginable). In order to establish the timing of pain, the patients were asked about the total duration of pain with a score higher than 3.
They were also asked about the administration of analgesics in the period up to the point of interview, and the answers were checked against patient records and discharge reports. Hospital-prescribed analgesics for the period after discharge were registered. All patients' discharge reports were read to obtain information on opioid prescribing and any plans for tapering or cessation.