Background Our study sought to externally validate the Infant Scalp Score (ISS) within an international pediatric emergency department (PED) setting. The ISS for pediatric Closed Head Injury (CHI), includes age, hematoma localization, and size, and has the potential to predict the presence of Traumatic Brain Injury (TBI) on computed tomography. We aimed to describe a potentially low risk cohort of children younger than 24 months with CHI and scalp hematomas, where clinicians may limit diagnostic radiation exposure to this vulnerable patient population. Methods This single-center retrospective study was conducted in Gazi University. Faculty of Medicine, Pediatric Emergency Department, a tertiary trauma care hospital. We reviewed patients (< 24 months) with CHI and scalp hematoma who visited the PED of our institution between January 1, 2019, and June 30, 2021 for rates of TBI and clinically important TBI (ciTBI). Results 380 cases met inclusion criteria for this study. The median age was 11 months and 58.7% were male children. 121 (31.8%) patients underwent CT, and 57% (n:69) of these studies were normal. TBI on CT was found in 26 (21.5%) patients with ciTBI was detected in 5 (1.3%) patients. All children with TBI were noted to have ISS scores of >= 5. Hematoma location OR 18.9 (95% CI, 3.4-105.1) and hematoma size OR 3.0 (95% CI, 1.2-7.3) were positively associated with presence of TBI. Conclusions Children with ISS scores of >= 5 were noted to have increased rates of both TBI and ciTBI. CHI related scalp hematomas located in the temporal/parietal region or with a size greater than 3 cm were associated with increased rates of TBI. Within the context of this study, ISS scores of 4 or less represented a lower risk for TBI and ciTBI. Future research on this potentially low risk pediatric CHI cohort is needed.