Complex care for kids Ontario: protocol for a mixed-methods randomised controlled trial of a population-level care coordination initiative for children with medical complexity.

Introduction: Technological and medical advances have led to a growing population of children with medical complexity (CMC) defined by substantial medical needs, healthcare utilisation and morbidity. These children are at a high risk of missed, fragmented and/or inappropriate care, and families bear extraordinary financial burden and stress. While small in number (<1% of children), this group uses ~1/3 of all child healthcare resources, and need coordinated care to optimise their health.