Hard Evidence: Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study

From BMJ:

Suzanne P McEvoy, senior research fellow1, Mark R Stevenson, professor of injury prevention1, Anne T McCartt, vice president, research2, Mark Woodward, professor of biostatistics1, Claire Haworth, research nurse3, Peter Palamara, senior research officer3, Rina Cercarelli, senior research fellow3

1 The George Institute for International Health, University of Sydney, PO Box M201, Sydney, NSW 2050, Australia, 2 Insurance Institute for Highway Safety, Arlington, VA, USA, 3 Injury Research Centre, University of Western Australia, Crawley, WA 6009, Australia

Correspondence to: S McEvoy smcevoy@thegeorgeinstitute.org

Objectives To explore the effect of drivers' use of mobile (cell) phones on road safety.

Design A case-crossover study.

Setting Perth, Western Australia.

Participants 456 drivers aged ≥ 17 years who owned or used mobile phones and had been involved in road crashes necessitating hospital attendance between April 2002 and July 2004.

Main outcome measure Driver's use of mobile phone at estimated time of crash and on trips at the same time of day in the week before the crash. Interviews with drivers in hospital and phone company's records of phone use.

Results Driver's use of a mobile phone up to 10 minutes before a crash was associated with a fourfold increased likelihood of crashing (odds ratio 4.1, 95% confidence interval 2.2 to 7.7, P < 0.001). Risk was raised irrespective of whether or not a hands-free device was used (hands-free: 3.8, 1.8 to 8.0, P < 0.001; hand held: 4.9, 1.6 to 15.5, P = 0.003). Increased risk was similar in men and women and in drivers aged ≥ 30 and < 30 years. A third (n = 21) of calls before crashes and on trips during the previous week were reportedly on hand held phones.

Conclusions When drivers use a mobile phone there is an increased likelihood of a crash resulting in injury. Using a hands-free phone is not any safer.