PDSA cycles: the five PDSA cycles illustrated with the main summary changes listed for each stage. ED, emergency department; PDSA, plan, do, study, act; SpR, specialist registrar. PDSA cycles: the five PDSA cycles illustrated with the main summary changes listed for each stage. ED, emergency department; PDSA, plan, do, study, act; SpR, specialist registrar. Alexander Carpenter, and Sabrina Sargent BMJ Open Qual 2018;7:e000260 © Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.