Drivers are becoming an even bigger risk to riders as they move from using their phones just for talking to more distracting uses such as texting.
The act of manipulating a device in the hand has grown by 57 per cent since 2014.
During the same period drivers were less likely to be seen simply holding a mobile phone or talking on a hand-held phone.
The findings resulted from a study in the US where observers were stationed on the roadside in both 2014 and 2018 on straight stretches of roads, at signalised intersections and at roundabouts.
Observers noted nearly 12,000 drivers in the 2018 survey and more than 14,000 drivers in 2014 during the morning, afternoon or early evening on weekdays.
About 23% were engaged in various distracting behaviours. As well as phone use drivers were observed eating, drinking, smoking, using devices other than a phone, reading newspapers and so on.
"The latest data suggest that drivers are using their phones in riskier ways," says David Kidd, who co-authored the study and is a senior research scientist with the Highway Loss Data Institute.
"The observed shift in phone use is concerning because studies consistently link manipulating a mobile phone while driving to increased crash risk."
Phone use affects how drivers scan and process information from the roadway. Drivers generally take their eyes off the road to dial, send texts and browse the web on a hand-held phone — all activities that fall under the rubric of manipulating the phone.
Drivers engaged in mobile phone conversations tend to concentrate their gaze toward the centre of the roadway, but their attention still may be diverted from driving and make it difficult for them to process what they are looking at.
Research has established that although all iPhones since 2017 can automatically block calls when driving, only about 20 per cent of drivers permit the feature to operate.
Paradoxically, 75% of drivers had used the feature and did not find it annoying, yet many switched it off because they were afraid of missing important calls.
In a Bicycle Network study, 35.7 per cent of bike riders surveyed see distracted driving every time they ride and 78.9 per cent have been involved in a 'near-miss' they believe was caused by distracted driving.
In February 2019, Bicycle Network outlined recommendations to address distracted driving in a submission to the National Transport Commission who are investigating ways to regulate the safe use of technology devices as part of the road rules.
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