New York: Middle-aged drivers are at higher risk of crashes because they use their cellphones regularly while driving, a study has found.

‘Unfortunately, we weren't surprised to see that relatively few people understand the risks of distracted driving,’ said lead author Jessa Engelberg from University of California-San Diego.

The researchers were surprised to find that the presence of children in the car did not affect drivers' behaviour.

Drivers continued to use their mobile phones with children as passengers, even with older children that were more likely to copy their driving behaviour.

A driver's crash risk is eight times higher if they are texting on a cellphone and, despite seeming safe, talking hands-free makes drivers four times more likely to be involved in a crash, previous studies suggest.

The researchers modified a survey to find out more about the driving behaviours of middle-aged adults (30-64 years old).

The results revealed that 75 percent of participants talk on cellphones hands-free, and almost 90 percent of them consider themselves capable or very capable drivers while doing so.

Less than 30 percent of participants knew that talking on a hands-free phone increases the risk of crashing to the same degree as driving at the legal alcohol limit.

‘The thing about middle-aged drivers is their passengers tend to be minors, and there's an issue of modelling if the adults are teaching them how to drive,’ said co-author professor Linda Hill.

More than one-third of participants said they felt pressured to answer work calls while driving, suggesting that there is an opportunity to reduce distracted driving by working with companies to educate both the employers and their employees.