In a joint collaboration of the Centers for Education and Research on Therapeutics (CERTS) at The University of Pennsylvania and the M.D. Anderson Cancer Center, this study proposes to a) combine detailed but under-utilized existing large datasets and b) collect new primary data; together, resulting two data resources will advance our ability to describe, study, and understand the effectiveness and safety of pharmaceuticals received by pediatric patients in hospitals, and how to improve the safe use of over-the-counter (OTC) acetaminophen in home settings.