Is it really good to talk? Testing the impact of providing concurrent verbal protocols on driving performance

Abstract

Questions have been raised regarding the impact that providing concurrent verbal protocols has on task performance in various settings; however, there has been little empirical testing of this in road transport. The aim of this study was to examine the impact of providing concurrent verbal protocols on driving performance. Participants drove an instrumented vehicle around a set route, twice whilst providing a concurrent verbal protocol, and twice without. A comparison revealed no differences in behaviour related to speed, braking and steering wheel angle when driving mid-block, but a significant difference in aspects of braking and acceleration at roundabouts. When not providing a verbal protocol, participants were found to brake harder on approach to a roundabout and accelerate more heavily coming out of roundabouts. It is concluded that providing verbal protocols may have a positive effect on braking and accelerating. Practical implications related to driver training and future research are discussed. Practitioner Summary: Verbal protocol analysis is used by ergonomists to understand aspects of cognition and decision-making during complex tasks such as driving and control room operation. This study examines the impact that it has on driving performance, providing evidence to support its continued use in ergonomics applications.

Good intentions: drivers’ decisions to engage with technology on the road and in a driving simulator

“…Periods of comparable speed limit and road curvature were compared across the route for the analysis of speed when they were providing verbal reports and when they were not. Areas where external sources may have influenced the drivers speed were removed such as intersections on the A road and junction exits on the motorway, as well as 100 m before and after them (Salmon et al 2017). The speed on the motorway and A road were compared separately to assess if there were any differences in the metrics between these road types.…”

“…The assessment of intention to engage, rather than making the driver physically engage, mitigated some of the safety concerns of studying the behaviour in the real world. Furthermore, Salmon et al (2017) found that the use of verbal protocols in the real-world driving setting may actually enhance driving performance and safety, with driving speed or control unaffected and breaking/acceleration at junctions improving (Salmon et al 2017). These findings, however, relate to the continuous verbal reports of drivers to assess the drivers' situational awareness, rather than assessing their decision-making process.…”

To stop or not to stop: Contrasting compliant and non-compliant driver behaviour at rural rail level crossings

“…Throughout the test route participants provided a concurrent verbal protocol to support assessment of their situation awareness (Salmon et al, 2014b) and were prompted to resume their verbal protocol if they became silent for extended periods. A recent on-road study undertaken to test the impact of providing a concurrent verbal protocol on driver behaviour found no adverse impacts on driving performance (Salmon et al, 2017).…”

A systematic review on sensor-based driver behaviour studies: coherent taxonomy, motivations, challenges, recommendations, substantial analysis and future directions

“…Lyu et al (2019) have explored the effect of advanced driver assistance systems (ADAS) on braking behaviour and driving performance in lane-changing scenarios. The last article in this category (Salmon et al, 2017) examines the impact of providing concurrent verbal protocols on driving performance, on two different locations, i.e. signalized intersections and roundabouts.…”