A classic study found that the replacing the usual naming convention for newborns ("Babygirl" or "Babyboy") with one incorporating the mother's first name (e.g., "Marysgirl" or "Marysboy") reduced wrong-patient errors. Based on this finding, The Joint Commission issued a National Patient Safety Goal (NPSG) requiring the use of distinct naming systems for newborns. The authors of this study noted that the new standard would still leave multiple-birth infants vulnerable to wrong-patient errors, as most hospitals adopted naming standards that left room for confusion between infants (e.g., twin infants might be named "Marysgirl1" and "Marysgirl2"). Researchers examined the rate of wrong-patient errors in six neonatal intensive care units of two health systems that used the NPSG recommended naming conventions, comparing multiple-birth infants to singleton infants. They measured wrong-patient errors by tracking the rate of orders that were retracted and then immediately reordered for a different patient. The rate of wrong-patient errors was significantly higher among multiple-birth infants, most of which could be explained by intrafamilial errors (e.g., a medication was ordered for one twin when intended for another). The accompanying editorial points out that this study is an important example of carefully assessing the real-world impact of novel policies; in this case, the NPSG likely does protect against wrong-patient errors for singleton infants, but not for multiple-birth infants.