Cost-Effectiveness of Rule-Guided Head Computed Tomography for Pediatric Head Injury: An Economic Modeling Study Using a Nationwide Claims Database.

Aim: To evaluate the cost-effectiveness of applying the Pediatric Emergency Care Applied Research Network (PECARN) head injury clinical decision rules versus usual care in Japan. Methods: We developed a public payer-perspective decision tree model by comparing PECARN rule-guided and usual-care computed tomography (CT) strategies for children aged 0-15 years with head injuries. The model captured short-term pathways (clinically important traumatic brain injury [ciTBI], CT use, admission or discharge, and surgery) and lifetime radiation-induced intracranial malignancy risk. Transition probabilities for the PECARN rule were obtained from a multicenter Japanese validation study, and usual-care transitions and costs were estimated from the Japan Medical Data Center (JMDC) nationwide claims database (2012-2019). Life-years were assessed over a lifetime. Uncertainty was explored using one-way and probabilistic sensitivity analyses, and scenario analyses assessed parameters, facility type, short-term hospitalization, and baseline CT utilization. Results: In the base-case analysis, the PECARN rule resulted in lower costs (¥11,391 vs. ¥12,148) and slightly higher effectiveness (39.41303 vs. 39.41296 life-years) than usual care. In probabilistic sensitivity analysis, the PECARN rule was cost-effective in 99.98% of simulations at a willingness-to-pay threshold of ¥5,000,000 per life-year. CT rates among children without ciTBI influenced the net monetary benefit most. Scenario analyses showed that the findings varied by facility type and baseline CT utilization. Conclusion: In average hospital-based usual care in Japan, use of the PECARN rule was associated with lower expected healthcare costs without meaningful loss of effectiveness and may support efficient resource use and reduced radiation exposure.