Nurses were the professional group most often reporting medication errors, and older patients were most often affected in the medication error reports analyzed for this study (Friend, 2011). The most common problems at Center A, where traditional pen-and-paper prescribing methods were used, were omission of medications or doses revealed by type of medication errors, incorrect dose, concentration, or frequency, and incorrect documentation; and incorrect documentation and omission were the most common problems associated with medication errors at Site B where electronic MMS was introduced (Friend, 2011). Reports of problems such as wrong drug, wrong dose, intensity or frequency, quantity, wrong route, wrong drug, and missed dose were less frequent in Site B (Friend, 2011). The reduced incidence of omission errors at Site B supports the hypothesis that an advantage of MMS is the easy identification of patient needs at each time point of the medication cycle. Although fewer omission errors were found at site B where MMS was introduced, there was a relatively high frequency in incident reporting of medication errors related to both omission and incorrect dose, strength, and frequency in both the sites (Friend, 2011). This finding supports claims that, despite a reduction in omission errors, dosing errors are still prevalent with a computerized system and minimizing this risk may require consideration of alternative or additional strategies to the introduction of MMS (Friend, 2011 ). These findings suggest that clinicians may have experienced difficulty prescribing the use of MMS, which may be partly explained by the relative newness of MMS in a new hospital site. Similarly, research has asserted a causal link between MMS and medication errors, attributed to electronic systems that were not very useful or easy to use by medical staff, generating human-machine interface errors and workflow problems that they were not consistent with usual pen and usage methods. paper drug