ObjectivesTo compare the success rates and ease of use of three intraosseous (IO) access devices used in term neonates.DesignA three-arm randomised controlled simulation study was conducted.SettingA simulation laboratory.ParticipantsSeventy-two paediatric residents completing their emergency department rotation as part of their residency training, and 20 paediatric specialists.InterventionUsing an animal bone model, the one-attempt success rate of the EZ-IO drill, the NIO-I needle and the Jamshidi needle was compared. Uncooked Cornish Hen bones were used because of their similarity in length and diameter to the bones of neonates. Participants were asked to record the perceived ease of use of their assigned device using a 5-point Likert Scale.Main outcome measureThe main outcome was the visualisation of flow emerging from the distal end of the bone, and perceived ease of use of the three IO devices.ResultsThe EZ-IO, NIO-I and Jamshidi groups included 30, 31 and 31 participants, respectively, with median (IQR) years of experience of 3 (2–5), 3 (2–6) and 4 (3–5) years. Participants had significantly lower one-attempt success rates with the EZ-IO drill than with the NIO-I and the Jamshidi needles (14 of 30 (46.7%) vs 24 of 31 (77.4%); p=0.016, and 14 of 30 (46.7%) vs 25 of 31 (80.7%); p=0.007, respectively). The median (IQR) ease-of-use score of the EZ-IO drill was higher than that of the NIO-I and Jamshidi needles (5 (4–5) vs 4 (4–5); p=0.008, and 5 (4–5) vs 4 (3–4); p=0.0004, respectively).ConclusionsAlthough easier to use, the EZ-IO drill demonstrated lower success rates than the IO needles in establishing IO access on a neonatal bone model.