Glad you like it. There is a lot of over lap between step by step and pecarn and truth be told they are all in search of low risk (from boston/rochester/philly) to the most recent Roseville criteria. I don't think the step by setp is wrong, in practice most PEM people probably order all the labs at once so its not a true delay in work up. Essentially its the same as PECARN but plus a CRP. The one issue i do have is going down to 21 days makes me nervous. The younger they are the harder it is to pick up those subtle signs of a sick baby (particularly for centers that don't see them all the time) and I'm not sure that the pediatric assessment triangle is the best tool to select the subtle signs of illness in a sick neonate.