Avoiding hospital IDs that say “baby boy” or “baby girl” when parents haven’t chosen a first name for their newborn may help reduce medical errors, a study suggests.

As a marker of potential mistakes, researchers analyzed how often doctors order tests, procedures or drugs for one newborn baby and then quickly retract it and place the same order for a different newborn.

At Montefiore Health System in the Bronx, in two neonatal intensive care units (NICUs), they compared this so-called “retract and reorder” rate for one year before and after the hospital changed its ID system for newborns.

In the old system, generic IDs showed only the infant’s gender and last name, such as “babygirl Johnson.”

In the new system, launched in July 2013, the babies’ IDs also incorporated the mother’s first name, such as “Wendysgirl Johnson.”

During the first year of the new IDs, the retract and reorder rate was about 36 percent lower than it was during the last year under the old system.

Doctors’ computer orders counted as retract and reorder entries if a physician retracted a request within 10 minutes of making it and then placed an identical order for a different patient.

“We call this an ‘oops’ measurement because these are near misses, and the good news here is that the findings suggest hospitals can decrease these errors by more than a third by switching to a new naming system,” said lead study author Dr. Jason Adelman, patient safety officer at Montefiore.

A previous study found that about 11 percent of medical errors in NICUs are due to patient misidentification, Adelman and colleagues report in the journal Pediatrics. Part of the problem is that many newborns in the NICU have similar last names and birth dates, the authors note.

Along with changing the system for singleton births, Montefiore also switched IDs for multiples, incorporating not just the mother’s first name but also a number. Twins, for example, might now have IDs that say “1Judysboy” and “2Judysboy.”

During the study period, under the old naming system, there were 157,857 orders placed for 1,115 babies, while there were 142,337 orders for 1,067 infants under the new guidelines.

For every 100,000 orders, the overall retract and reorder rate fell from 59.5 with the old IDs to 37.9 with the new ones, the study found.

The reduction was more pronounced for orders placed by doctors in training, and for male babies.

One shortcoming of the study is that it didn’t have enough newborns from multiple births to measure how much the new naming system might reduce errors for twins or triplets, who may be at increased risk for mistakes under older ID systems, the researchers acknowledge.

It’s also possible that because doctors knew about the new naming system and the rationale behind it, they became more careful with their orders as a result, the authors note.

Even so, this naming format has proved effective elsewhere, said Dr. Amir Kushnir, head of neonatology and the NICU at Baruch Padeh Medical Center, Poria Tiberias, Israel.

Israeli government hospitals all register babies in the format “WendysGirl Smith,” Kushnir, who wasn’t involved in the study, said by email.

“All patients in the hospital are at risk of misidentification, but the risk of newborns being misidentified is stronger because demographic details of those babies are very similar,” Kushnir said.