Intravenous solutions may cause adverse drug events more quickly than oral medications. And some medications administered intravenously have higher risks than others of causing severe adverse drug events. Double-checks can be a valuable safety mechanism to ensure that all data and orders are correct before anyone acts on them. For the double-checks to be effective, at least two qualified people must perform them independently. Checking together runs the risk that both people will make the same error (for example, one person might read the dosage aloud incorrectly and the other might automatically agree).