Design: This study will be a crossover randomized controlled trial in the setting of the simulation laboratory. Subjects will include pediatric residents and pediatric subspecialty residents. Exclusion criteria will include any medical condition or medication that can have a significant impact on cortisol levels. The residents will be randomized using sealed envelopes to perform a neonatal ETI in a low or a high stress environment, and then crossover to the other on a separate day. Stress will be created and standardized by using audio alarms, third party supervisors and simulated manikin instability. Level of stress of participants will be assessed at baseline during a lecture, upon arrival to the simulation center and after the simulated procedure. This will be done using salivary cortisol, heart rate and the STAI questionnaire. ETI procedures will be videotaped and performance will be assessed by two external reviewers using a validated checklist.