“The Medication Regimen Complexity Index (MRCI) is a validated tool that assesses medication regimen complexity in adult and geriatric populations with polypharmacy, and it has the potential to be extrapolated to the pediatric population,” James A. Feinstein, MD, MPH,of the Adult and Child Consortium for Health Outcomes Research and Delivery Science (ACCORDS) at the University of Colorado and Children’s Hospital Colorado, and colleagues wrote in JAMA Network Open.