SINGAPORE - Whenever she reaches to pick up her newborn son, a tag on Madam Kho Tat Sing's wrist "chimes".
This radio frequency identification (RFID) device is an added security feature at Mount Elizabeth Hospital. The same technology is used for wave-through payments with credit cards.
Madam Kho's husband, Mr Roy Loh, was tickled by the "very interesting ring tone" that sounds whenever his wife is near their son.
But the first-time father said that even with the device, the nurses ask for the mother's name and identity card number and check them against both tags on the boy's ankle.
Madam Kho said she did worry when she heard of the baby mix- up at KK Women's and Children's Hospital (KKH). So she is glad to have both the wrist tag and the nurses conducting manual checks.
An alarm goes off in the tag if the mother carries the wrong baby.
Other hospitals, including those other than KKH in the Parkway group, use the same checking system as KKH.
But obstetricians said they have never heard of two babies getting mixed up before in Singapore. Private obstetrician Jothi Kumar said that in his more than 30 years' experience, "this is the first time I've heard of such a thing happening".
He said the multiple manual checks are a routine procedure that has worked well. In this case, "there was a slip-up somewhere".
While he thought the wrist tag system at Mount Elizabeth Hospital was interesting, he said: "If the alarm doesn't work, then they're in trouble."
Dr Abdul Aziz said he was shocked to hear of the recent mix-up.
The doctor, who has more than two decades' experience, asked: "How can one baby have two different tags?"
He said that if a tag falls off at Parkway East, where he delivers babies, two nurses are needed to verify that the replacement matches the one still on the infant's ankle.
"And if both should fall off, which is very rare, then every baby in the nursery has to be checked before the baby is re-tagged," he said.
Most Singapore hospitals - including KKH - have accreditation from America's Joint Commission International, which shows they are of a certain standard.
Dr Aziz said one of the commission's requirements is that both ankle tags are checked every single time the baby leaves the nursery.
A spokesman for National University Hospital, which uses the same procedure as KKH, said that before they are discharged, newborns are brought to their mother and both tags verified against hers.
Only then is the baby dressed to be taken home. She added: "All staff are to comply with this step - even if the baby is sleeping."
Dr Chia Shi-Lu, an orthopaedic surgeon and member of the Government Parliamentary Committee for Health, said: "Identification is checked, double-checked, triple-checked... then verified again with the patient."
But in his experience, when a system is based on human verification, mistakes can occur. "Sometimes a patient can be asked to verify his identity and he or she can reply affirmatively to a completely different name."
He suggested using "both human and electronic identification systems" in case one fails.
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