Elsevier

Accident Analysis & Prevention

Volume 39, Issue 6, November 2007, Pages 1170-1176
Accident Analysis & Prevention

The contribution of passengers versus mobile phone use to motor vehicle crashes resulting in hospital attendance by the driver

https://doi.org/10.1016/j.aap.2007.03.004Get rights and content

Abstract

There is evidence that mobile phone use while driving (including hands-free) is associated with motor vehicle crashes. However, whether the effects of mobile phone use differ from that of passengers in the vehicle remains unclear. The aim of this research was to estimate the risk of crash associated with passenger carriage and compare that with mobile phone use. A case-control study (‘passenger study’) was performed in Perth, Western Australia in 2003 and 2004. Cases were 274 drivers who attended hospital following a motor vehicle crash and controls were 1096 drivers (1:4 matching) recruited at service stations matched to the location and time and day of week of the crash. The results were compared with those of a case-crossover study (‘mobile phone study’) undertaken concurrently (n = 456); 152 cases were common to both studies. Passenger carriage increased the likelihood of a crash (adjusted odds ratio (adj. OR), 95% confidence interval (95% CI), 1.6, 1.1–2.2). Drivers carrying two or more passengers were twice as likely to crash as unaccompanied drivers (adj. OR 2.2, 95% CI 1.3–3.8). By comparison, driver's use of a mobile phone within 5 min before a crash was associated with a fourfold increased likelihood of crashing (OR 4.1, 95% CI 2.2–7.7). Passenger carriage and increasing numbers of passengers are associated with an increased likelihood of crash, though not to the same extent as mobile phone use. Further research is needed to investigate the factors underlying the increased risks.

Introduction

There is evidence to suggest that mobile phone use contributes to driver distraction and can increase the likelihood of having a serious motor vehicle crash (McEvoy et al., 2005). However, there is controversy about the extent to which mobile phone use while driving differs from passenger carriage (Rapid responses to McEvoy et al., 2005). Mobile phone use while driving has a number of potentially distracting effects: cognitive (arising from the conversation), visual (from looking for the phone or at the display or keypad), auditory (through listening to the conversation) and manual (from holding the phone or dialling a number). Passengers can cause similar distractions namely, cognitive (from conversing), visual (if the driver turns to look at a passenger), auditory (from listening to a conversation) and even manual (for example, a driver passing a drink to a child). Moreover, passenger carriage may have additional effects on the driver, including peer influence. Under certain circumstances, any of these could lead to an adverse event.

To date, only a few studies have compared driving impairment resulting from remote mobile phone conversations versus conversations with passengers; most of which have been laboratory-based driver simulator studies (Hunton and Rose, 2005, Gugerty et al., 2004, Consiglio et al., 2003). Generally, these studies have indicated that driving impairment occurs for both situations. However, the findings are inconsistent on whether the extent of the driving impairment differs significantly between the two conditions. Hunton and Rose (2005) found that hands-free mobile phone use interfered more with driving than passenger conversations. By contrast, Consiglio et al. (2003) found that conversation significantly lengthened mean reaction time in each of the following three situations: conversing with a passenger, conversing with a hand-held mobile phone and conversing with a hands-free mobile phone. The mean reaction times between these situations were not significantly different.

In order to provide epidemiological evidence of the effects of passenger carriage and mobile phone use on road safety, we conducted two studies to contrast the risk associated with each factor. Using drivers involved in motor vehicle crashes requiring presentation to hospital, a case-control study and a case-crossover study were undertaken. The former (henceforth named the ‘passenger study’) examined the role of passenger carriage, and number and age group of passengers on motor vehicle crashes. The findings were compared with risk estimates of the effect of mobile phone use on motor vehicle crashes derived from the case-crossover study (McEvoy et al., 2005), henceforth named the ‘mobile phone study’.

Section snippets

Setting

Both studies were conducted in metropolitan Perth, the capital city of the state of Western Australia. The population of Perth is 1.3 million, with close to 1.1 million aged ≥15 years (Australian Bureau of Statistics, 2002). Based on driver's licence statistics, it is estimated that 75% of people aged ≥17 years in Perth hold a driver's licence. There were no passenger or hands-free mobile phone restrictions in place in Western Australia at the time of the studies. Hand-held mobile phone use while

Passenger study

Of the 347 drivers approached following a crash, 39 declined participation and 34 met an exclusion criterion. The remaining 274 drivers were interviewed. The case response rate was 88% (274/313). Among the 2267 drivers approached at service stations, 1145 declined participation and 26 were ineligible. The remaining 1096 drivers were interviewed. The control response rate was 49% (1096/2241). Accordingly, there were 1370 participants in the case-control study, 274 cases and 1096 controls (1:4

Discussion

Drivers with passengers were almost 60% more likely to have a motor vehicle crash resulting in their hospital attendance, irrespective of their age group. The likelihood of a crash was more than doubled in the presence of two or more passengers. Nonetheless, the risk is considerably lower than that conferred by mobile phone use while driving. In contrast to mobile phone use, passengers, with some exceptions, are generally aware of the road conditions and can moderate their conversation as

Acknowledgements

The contribution of Ms. Claire Haworth, Ms. Margaret Hocking, Mr. John Anderson and Mr. Frank West at The University of Western Australia is acknowledged. The studies relied upon the support of the participating hospitals, St. John Ambulance Service, and telecommunication companies (mobile phone study) and participating service stations (passenger study). The research was funded by the Motor Accidents Authority of New South Wales (Australia) and Insurance Institute for Highway Safety (United

References (22)

  • Australian Bureau of Statistics, 2002. 2001 Census of Population and Housing. Commonwealth of Australia,...
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