BackgroundTrainees aiming to specialize in Neonatal Perinatal Medicine (NPM), must be competent in a wide range of procedural skills as per the Royal College of Canada. While common neonatal procedures are frequent in daily clinical practice with opportunity to acquire competence, there are substantial gaps in the acquisition of advanced neonatal procedural skills. With the advent of competency by design into NPM training, simulation offers a unique opportunity to acquire, practice and teach potentially life-saving procedural skills. Little is known on the effect of simulation training on different areas of competence, and on skill decay.MethodsWe designed a unique simulation-based 4-h workshop covering 6 advanced procedures chosen because of their rarity yet life-saving effect: chest tube insertion, defibrillation, exchange transfusion, intra-osseus (IO) access, ultrasound-guided paracentesis and pericardiocentesis. Direct observation of procedural skills (DOPS), self-perceived competence, comfort level and cognitive knowledge were measured before (1), directly after (2), for the same participants after 9–12 months (skill decay, 3), and directly after a second workshop (4) in a group of NPM and senior general pediatric volunteers.ResultsThe DOPS for all six procedures combined for 23 participants increased from 3.83 to 4.59. Steepest DOPS increase pre versus post first workshop were seen for Defibrillation and chest tube insertion. Skill decay was evident for all procedures with largest decrease for Exchange Transfusion, followed by Pericardiocentesis, Defibrillation and Chest Tube. Self-perceived competence, comfort and cognitive knowledge increased for all six procedures over the four time points. Exchange Transfusion stood out without DOPS increase, largest skill decay and minimal impact on self-assessed competence and comfort. All skills were judged as better by the preceptor, compared to self-assessments.ConclusionsThe simulation-based intervention advanced procedural skills day increased preceptor-assessed directly observed procedural skills for all skills examined, except exchange transfusion. Skill decay affected these skills after 9–12 months. Chest tube insertions and Defibrillations may benefit from reminder sessions, Pericardiocentesis may suffice by teaching once. Trainees’ observed skills were better than their own assessment. The effect of a booster session was less than the first intervention, but the final scores were higher than pre-intervention.Trial RegistrationNot applicable, not a health care intervention.