Doctors at the capital’s Preah Kossamak Hospital are still dealing with plenty of traffic collision-related head injuries, but this week took note of a new phenomenon – a significant jump in the number of patients who were wearing helmets when those accidents occurred.

The data seems to suggest a direct correlation between helmet usage and this year’s concerted effort to enforce the new Traffic Law, said Dr Kee Park, a Harvard University Paul Farmer Global Surgery Scholar and consultant neurosurgeon at the hospital.

“The weakness of this data is that it cannot be generalised for all Cambodians,” Park cautioned. But “this could be an indication that the overall helmet usage is increasing”.

Since 2013, doctors at Preah Kossamak have been collecting data on head trauma cases from motorbike accidents, noting which patients were wearing helmets and which weren’t.

In 2015, doctors found that the average number of patients who were wearing a helmet was about 13 per cent, according to the data.

This year so far, excluding January, the rate of patients who were wearing a helmet has almost doubled to 24 per cent. The hospital saw 355 motorbike accident-related head-injury patients in 2015, and 132 so far this year.

Ear Chariya, director of the Road Safety Institute, said while the “data was quite interesting”, a broader study was needed in order to get a better idea on how much impact the law is having.

“I think it’s a small piece of the overall picture,” he said, adding that the law is “not widely enforced in the whole country”.

It’s unknown how many of the total number of head trauma cases come to Preah Kossamak, Park said, but the hospital is one of only three in Phnom Penh staffed with neurosurgeons.

The data also does not address whether patients who were wearing a helmet were spared more severe head injuries than those who weren’t, Park added.

Studies have shown that if helmets don’t meet quality standards, they don’t protect motorists’ heads, Chariya said. “We need to encourage people to wear helmets, but also [show] how to choose a good one.”

A total of 18,352 people were fined for not wearing helmets in the first three months of enforcement of the new law, according to a National Police report released in March.

Additional reporting by Lay Samean