to the ED or a rehospitalization for adverse drug reaction (vomiting and/or diarrhea, dehydration, Clostridium difficile infection, allergic reaction, urticaria, anaphylaxis, drug-induced neutropenia, acute kidney injury, Stevens-Johnson syndrome, erythema multiforme, or other). – Return to the ED or a rehospitalization for PICC complication (fever evaluation, infection at the site of the PICC insertion, bloodstream infection, sepsis, thrombosis, or breakage, repair, adjustment, manipulation, or removal of the PICC line with or without insertion of a new line). – Composite of treatment failure, adverse drug reaction, and PICC line complication.