Crying as a Sign, a Symptom, and a Signal: Clinical, Emotional and Developmental Aspects of Infant and Toddler Crying

Ronald G. Barr, MDCM, FRCP-C Vancouver, British Columbia, Canada. Ronald G. Barr, MA, MDCM, FRCP-C, developed and tested prevention materials referred to as the Period of PURPLE Crying in collaboration with Marilyn Barr. He is the Canada Research Chair in Community Child Health Research at the University of British Columbia and Professor of Pediatrics in the Faculty of Medicine at UBC.