Background: Head injury is the most common cause of childhood morbidity and mortality worldwide. Mild head injury comprises 90% of cases of head injury in children. Head CT scans are few, expensive and have the side effect of ionizing radiation whose effect is potentiated in children and also associated risk of sedation that is often required when doing CT scans in young children. The decision to order CT scans of the head is thus made on the basis of clinical decision rules of which the PECARN CT head rule has been found to be most sensitive and useful. Objectives: Primary: To determine the proportion of head CT scans done for children with mild head injury after the introduction of PECARN head CT rules compared to the period before. Secondary: To determine disposition of patients from casualty after introduction of the PECARN head CT rules as compared to the period before and to determine the probability of neurosurgical intervention in patients under 18 years with mild head injury at AKUH (N). Methodology: Study design: A before and after quasi experimental study with a study population including all children under 18 years presenting to the AKUH (N) with mild head injury and a Glasgow coma scale of 14 and above on presentation. Sample size was 85 Results: A total of 42 patients files were analyzed in the before study while 43 patients were selected for the after study. The median age was 5 years. The proportion of head CT scans reduced from 56% in the before group to 33% in the after group with no missed clinically significant traumatic brain injury. More patients were discharged home after evaluation in the after group (81%) than in the before group (58%). Conclusions: The number of head CT scans ordered for children with mild head injury reduced after the introduction of the PECARN head CT rule, without missing any clinically significant traumatic brain injury.