Amelung S, et al. - This study aspired to determine the ICD-10 codes coding for potentially preventable in-hospital adverse drug events (ADE) which exerted an impact on the length of hospital stay (LOS) and thereby the patients' well-being and cost. It was illustrated that the inpatients with adverse drug events (ADE) codes referring to inhospital, potentially preventable ADE exceeded the maximum hospital stay fully reimbursed by insurance companies. This data indicated unnecessary long and costly inpatient stays.