Head injuries are common among children and adolescents, with many of them assessed in emergency departments each year. Most children recover fast, with full resolution of symptoms as headache, dizziness or fatigue. A few, however, develop life-threatening complications (such as bleedings in/around the brain). It can be difficult to swiftly and accurately identify these patients in the emergency department. To aid in this task, decision support tools has been developed.

The goal of this observational study is to evaluate a Scandinavian tool developed to aid in management of children with head injuries seeking care in an emergency department.

The main research question is:

- Are the Scandinavian guidelines for management of mild and moderate head trauma in children sensitive for patient-important outcomes?

Patients will be given the same treatment and recommendations for their head injury no matter if they participate or not in the study, as there is no intervention/ treatment group.

The doctor or nurse managing the child will collect information on patient history, signs and symptoms in the emergency department and management in an electronic case report form. Information on how the recovery period is collected both from medical records >1 month after the emergency department visit, as well as via electronic questionnaires sent to the guardian at 1 month, 3 months and 4 months after the injury via e-mail and/or text message. Long-term outcome will also be examined (>6 months).

Design:

This is a pragmatic, prospective, multicentre, observational study of children presenting with mild or moderate traumatic brain injury (TBI) in a general or paediatric emergency department (ED) at hospitals in Scandinavia. A complete data set for analysis including predictor variables and outcome data for the six guidelines included in the study will be registered (SNC2016, PECARN, CATCH, CHALICE, PREDICT, NICE23). There are no interventions as the study is observational. Attending physicians and nurses are instructed to manage children in accordance with the hospital's ordinary guidelines and follow local treatment traditions.

Study setting and population:

The study will be set in Sweden and Norway. Hospitals with different trauma capacities will participate; invitations are sent to units which on daily basis mange children with TBI in their department. Efforts are made to establish a representative distribution in participating centres. The coordinating centre is Halmstad Hospital in southern Sweden.

Data registration and follow-up:

Information on management in the emergency department including patient characteristics, injury type and mechanism, patient history, clinical examination results and current medications will be prospectively documented in a web- based case-report form by the triage nurse and/or physician on call.

One month after trauma, the local study coordinator will assess medical records and journals, screening for outcome measures as well as CT findings, when applicable. A follow-up questionnaire will be sent to guardian(s) 1 month, 3 months and 4 months after the child ́s head injury via e-mail and/or text message (long-term follow up at >6 months). Reminders will be re-sent if no answer is received, primarily by e-mail and then twice by text message.

All data will be registered in via web-based case report forms in Entermedic (Entergate AB). Pseudo-anonymized data will be extracted from database and imported to IBM SPSS® Statistics software version 28 for statistical analysis.

Biomarkers:

A sub-study on patients with intermediate risk for intracranial injury and GCS 14-15, in selected study centres will explore biomarkers as predictors for intracranial injury. Venous blood, capillary blood and saliva sample is sampled from the patient in the ED after written informed consent. Sampling is done within 12 hours from the time of the injury. Analysis of biomarker S100B and others, not yet specified, will be analysed in batch at end of sub-study period.

CT examinations:

CT scans are analysed by a board-certified radiologist on the centre where the exam is performed.

Statistics:

The accuracy of the (SNC) guidelines to predict the primary endpoint will be assessed by 95% confidence intervals (CI) for sensitivity, specificity, likelihood ratio, negative predictive value (NPV) and positive predictive value (PPV). Test performance for other internationally recognized clinical decision rules (PECARN, CATCH, CHALICE, NICE, PREDICT) will also be calculated both in application cohorts (defined by each rule specific inclusion and exclusion criteria) and in comparative cohorts (minor head injury cohort = all patients with GCS 13-15; all patient cohort). When assessing CDRs other than SNC16, both rule specific endpoints and in-study defined endpoints will be tested. Secondary endpoints will be assessed using the same methods. Biomarker analysis results in ROC curves for sensitivity / specificity and from these are specific cut-offs that maximize performance for negative predictive value (i.e., to avoid unnecessary CT examinations and/or admission) derived.

Sample size:

The investigators aim to include 5,300 children, but not more than more than 4 years of active enrolment.

Ethics:

Ethical approval was granted from the Regional Ethical Review Board in Lund (approval number 2017/238) and Ethical Review Board in Norway (approval number 1085). Informed verbal consent will be obtained and registered. Patients' data and social security number will be stored and handled accordingly to European Union General Data Protection Regulation (GDPR 2016/679) and applicable Swedish laws.

A detailed protocol describing study methodology and statistical methods will be published before end of inclusion.

Inclusion Criteria:

• Age <18 years.
• Minor and moderate blunt head trauma (GCS 9 - 15) seeking medical assessment in an emergency department at a study hospital in Sweden or Norway.
• Within 24 hours of trauma.
• Informed oral consent from one guardian, and child if older than 14 years old, after receiving oral and written information about study.

Exclusion Criteria:

• Patient and/or guardian does not wish to participate in the study.
• Patient included in other study that may affect the management/treatment in the emergency department.
• Penetrating head injury (as those will always receive a CT scan).
• Suspected child abuse / non-accidental trauma (NAT) denoted as suspected child abuse where the social services are informed (as they will always receive a CT scan).
• The patient is not a citizen in the participating country and hence difficult to follow up.

Target population is children in Scandinavia with recent minor and moderate head trauma seeking care on emergency departments within participating in study.

Sharing of de-identified data for all primary and secondary outcome measures will be considered on individual basis after main and secondary analysis has been completed.

Data will be available on reasonable request up to 10 years after study completion.

Investigators whose proposed use of the data has been approved by the study review committee and sharing of requested data is permitted by Swedish and European law.