Epidemiology of adverse drug events and medication errors in four nursing homes in Japan: the Japan Adverse Drug Events (JADE) Study.

In Japan, ADEs and MEs are common among elderly residents of NHs. The assessment and appropriate adjustment of medication preadmission and postadmission to NHs are needed to improve medication safety, especially when a single physician is responsible for prescribing most medications for the residents, as is usually the case in Japan.