Background <p>The national trauma plan defines common Norwegian criteria dictating which patients are met by a trauma team. Precise criteria are important to avoid undertriage and overtriage. Previous studies have indicated that both overtriage and undertriage fail to meet the goals of the Norwegian Trauma Plan, and the aim of the study was to investigate the performance of the new national criteria.</p> Methods <p>This is a retrospective cohort study of patients included in the trauma registry at Haukeland University Hospital between 2017 and 2021. Injury Severity Score (ISS) was extracted from the registry. Prehospital records were manually reviewed to determine which trauma criteria were met. The aim was to analyse how well the national trauma criteria predicted ISS &gt; 15, and if national goals of overtriage and undertriage were met.</p> Results <p>A total of 2508 patients were eligible for analysis, whereas 384 had an ISS &gt; 15, with a total overtriage of 81.1%. Forty-four patients had an ISS &gt; 15 without meeting the criteria, resulting in an undertriage of 11.5%. If hypothetically <i>4 Patient factors</i> was analysed as an individual criteria group, undertriage would have been 2.9%. Patients who did not meet any criteria had an overtriage of 97.6%. <i>Mechanism of injury (MOI)</i> predicted ISS &gt; 15 in nine of 333 patients, resulting in an overtriage of 97.3% for this criteria group. Hypothetical removal of the MOI criteria except <i>3.6 Fall</i> would in this data set eliminate 255 Trauma team activations (TTA) among patients with ISS &lt; 15.</p> Conclusions <p>Overtriage was high overall and across all criteria groups. Patients who triggered a TTA despite not meeting any criteria also demonstrated substantial overtriage. To optimize resource use, criteria with low positive predictive value could be assigned fewer resources or revised to reduce unnecessary activations. Our findings support re-evaluation of specific criteria, particularly those related to mechanism of injury.</p>