Objectives: The developmental stages of the clavicles are important for forensic age estimation purposes in adolescents. This study compares the 4-stage system to evaluate the ossification of the medial end of the clavicle as visualized by magnetic resonance imaging (MRI) and computed tomography (CT). As several forensic institutes routinely perform CT scans, the large amount of available data may serve as reference sample for MRI in specific cases. Material and methods: This prospective study included an MRI and CT scan of 47 autopsy cases performed prior to medico-legal autopsy (age range 12.9-27.5 years). All images were scored in blind trials using a 4-stage system by a trained observer. Results: Intra-observer agreements were substantial within (MRI: K=0.685, CT: K=0.611) and between modalities (K=0.644, p