A prospective study was conducted to validate the retrospective finding that adolescents (11 to 15 years old) with skull fractures were prone to develop acute traumatic intracranial hematoma (ICH). Over a 4-year period, 1178 consecutive adolescents attended the emergency room directly, of whom 760 were discharged well and 418 were admitted. All underwent skull x-ray studies. Immediate computerized tomography (CT) scans were performed in patients with Glasgow Coma Scale (GCS) scores of less than 15, in those with radiological and/or clinical evidence of skull fracture, and whenever clinically indicated. Of the 418 admitted patients, only 26 had skull fractures; 13 of these developed ICH. Four patients without skull fracture developed diffuse brain swelling. The remaining 401 patients were discharged after observation periods of up to 48 hours. Of the 13 patients with ICH, 10 had admission GCS scores of 15; however, four deteriorated rapidly and required urgent operation, and four remained stable but were operated on due to their large ICH. Two required conservative treatment only and both made good recovery. Three patients were in coma (GCS score less than or equal to 8) on admission. One patient had an epidural hematoma and made good recovery after surgery. Two developed delayed ICH after operations for associated systemic injuries despite initial CT showing diffuse brain swelling only, and both died despite evacuation of the ICH. Multivariate analysis showed that skull fracture was the only independent significant risk factor in predicting ICH in adolescents (sensitivity of 100% and specificity of 97%). A routine skull x-ray study is therefore mandatory in all head-injured adolescents and, if a skull fracture is detected, immediate CT may be performed for early detection of ICH.