October 2014

  1. How many people use cellphones to talk or text?

    Cellphone use in the United States has grown quickly during the past decade. There were about 336 million wireless cellphone subscribers as of December 2013. CTIA – The Wireless Association. 2014. CTIA's Wireless Industry Summary Report, Year-End 2013 Results. Washington, DC. Available: http://www.ctia.org/your-wireless-life/how-wireless-works/annual-wireless-industry-survey. Accessed: October 23, 2014. That's more than double the number of subscribers in December 2003. In 2013, people talked on cellphones for 2.6 trillion minutes and sent and received 1.9 trillion text messages. Texting has grown more rapidly than talking on cellphones but seems to be on the decline. The annual number of minutes spent talking on cellphones increased 19 percent from 2008 to 2013, while the annual number of text messages sent or received increased by more than 91 percent. However, the annual number of text messages sent or received declined 13 percent from 2012 to 2013.

  2. How frequently do drivers talk on the phone or text behind the wheel?

    A 2012 national observational survey found that 5 percent of drivers stopped at intersections were talking on hand-held phones at any moment during the day. National Highway Traffic Safety Administration. 2014. Driver electronic device use in 2012. Report no. DOT HS-811-884. Washington, DC: U.S. Department of Transportation. Combining this observational data with self-reported data on hand-held and hands-free phone use, the government estimates that 9 percent of drivers were having phone conversations during any moment of the day. This rate has held steady in recent years after nearly doubling between 2000 and 2005.

    Institute research examined the cellphone use of 105 Virginia drivers whose daily driving was monitored continuously for one year during 2003-04. Farmer, C.M.; Klauer, S.G.; McClafferty, J.A.; and Guo, F. 2014. Relationship of near-crash/crash risk to time spent on a cellphone while driving. Arlington, VA: Insurance Institute for Highway Safety. On average, drivers spent 7 percent of their driving time talking or listening to a cellphone. Another naturalistic study of drivers in Michigan conducted during 2009-10 also estimated that drivers talked on cellphones about 7 percent of the time, on average. Funkhouser, D. and Sayer, J. 2012. Naturalistic census of cell phone use. Transportation Research Record 2321:1-6. A naturalistic study conducted in Virginia and North Carolina during 2011 included only drivers who said they used their phones while driving every day; these drivers talked on a cellphone 11 percent of the time while driving. Fitch, G.A.; Soccolich, S.A.; Guo, F.; McClafferty, J.; Fang, Y.; Olson, R.L.; Perez, M.A.; Hanowski, R.J.; Hankey, J.M.; and Dingus, T.A. 2013. The impact of hand-held and hands-free cell phone use on driving performance and safety-critical event risk. Report no. DOT HS 811-757. Washington, DC: National Highway Traffic Safety Administration.

    Less is known about the frequency of texting behind the wheel. In a 2013 national telephone survey, about one-quarter of drivers reported sending a text message or e-mail while driving at least once in the past 30 days, and about three-quarters said they had read a text or e-mail. Hamilton, B.C.; Arnold, L.S.; and Tefft, B.C. 2013. Distracted driving and perceptions of hands-free technologies: finding from the 2013 traffic safety culture index. Washington, DC: AAA Foundation for Traffic Safety. National observation surveys indicate the rate of drivers texting and driving at any moment during the day is low but may be rising. In 2012, 1.5 percent of drivers were observed texting or otherwise manipulating hand-held devices. National Highway Traffic Safety Administration. 2014. Driver electronic device use in 2012. Report no. DOT HS-811-884. Washington, DC: U.S. Department of Transportation. That’s a 150 percent increase from 0.6 percent in 2009.

  3. Who is most likely to use a cellphone while driving?

    Younger drivers are more likely than older drivers to talk on phones and to text while driving. In a 2013 national telephone survey, about 72 percent of drivers 19-24 years old and 82 percent of drivers 25-39 years old said they had talked on a cellphone while driving at least once in the past 30 days, but only 51 percent of drivers 60-74 years old and 31 percent of drivers 75 and older said the same. A larger proportion of 19-24 and 25-39-year-old drivers also said they had read or sent a text or e-mail while driving at least once in the past 30 days compared with the proportion of drivers 60 and older who said they did. Hamilton, B.C.; Arnold, L.S.; and Tefft, B.C. 2013. Distracted driving and perceptions of hands-free technologies: finding from the 2013 traffic safety culture index. Washington, DC: AAA Foundation for Traffic Safety. In 2012, nearly 6 percent of drivers ages 16-24 observed in the daytime while stopped at intersections were talking on a hand-held cellphone, compared with 5 percent of drivers ages 25-69. In the same survey, about 3 percent of drivers ages 16-24 were observed manipulating a hand-held device, while only a little more than 1 percent of drivers ages 25-69 were observed doing the same. National Highway Traffic Safety Administration. 2014. Driver electronic device use in 2012. Report no. DOT HS-811-884. Washington, DC: U.S. Department of Transportation. A study analyzed random samples of naturalistic study data collected from small samples of adult drivers and newly licensed teenagers. There was no significant difference between the adult and teenage drivers in the percentage of clips where they talked on or listened to a hand-held or hands-free cellphone or dialed or reached for their phones. Klauer, S.G.; Guo, F.; Simons-Morton, B.G.; Ouimet, M.C.; Lee, S.E.; and Dingus, T.A. 2014. Distracted driving and risk of road crashes among novice and experienced drivers. New England Journal of Medicine 370:54-9.

    There is evidence that people who use cellphones more frequently while driving than other people are riskier drivers and engage in other risky driving behaviors more frequently. In an Institute study examining the cellphone use rates and near-crash and crash rates of drivers who were continuously monitored for one year, the drivers who spent the greatest amount of their driving time interacting with a cellphone also had the highest rates of near-crashes and crashes. Farmer, C.M.; Braitman, K.A.; and Lund, A.K. 2010. Cellphone use while driving and attributable crash risk. Traffic Injury Prevention 11(5):466-70. In an on-road study, drivers who reported frequent cellphone use drove faster, changed lanes more often and made more hard braking maneuvers than drivers who said they rarely used cellphones while driving. Zhao, N.; Reimer, B.; Mehler, B.; D’Ambrosio, L. A.; and Coughlin, J. A. 2012. Self-reported and observed risky driving behaviors among frequent and infrequent cell phone users. Accident Analysis and Prevention -  epub ahead of print. In a national survey of high school students of driving age, those who said they had sent or received at least one text message or email while driving in the past 30 days were more likely than other students to report not always using a safety belt as a passenger, riding with a driver who had been drinking, and driving after drinking. Olsen, E.O.; Shults, R.A.; and Easton, D.K. 2013. Texting while driving and other risky motor vehicle behaviors among U.S. high school students. Pediatrics 131(6):e1708-15.

  4. How does talking on a cellphone or texting while driving affect crash risk?

    Two separate epidemiological studies linked talking on a cellphone to a fourfold increase in the likelihood of a crash resulting in injury to the driver McEvoy, S.P.; Stevenson, M.R.; McCartt, A.T.; Woodward, M.; Haworth, C.; Palamara, P.; and Cercarelli, R. 2005. Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study. British Medical Journal 331(7514):428-30. or risk of a crash involving property damage but no injury. Redelmeier, D.A. and Tibshirani, R.J. 1997. Association between cellular-telephone calls and motor vehicle collisions. The New England Journal of Medicine 336:453-58. However, recent naturalistic research where drivers are continuously monitored and videotaped during daily driving suggests that the relationship between cellphone use and crashes is more complicated and that the estimates from these early epidemiological studies may be too high. Fitch, G.A.; Soccolich, S.A.; Guo, F.; McClafferty, J.; Fang, Y.; Olson, R.L.; Perez, M.A.; Hanowski, R.J.; Hankey, J.M.; and Dingus, T.A. 2013. The impact of hand-held and hands-free cell phone use on driving performance and safety-critical event risk. Report no. DOT HS 811-757. Washington, DC: National Highway Traffic Safety Administration. Klauer, S.G.; Guo, F.; Simons-Morton, B.G.; Ouimet, M.C.; Lee, S.E.; and Dingus, T.A. 2014. Distracted driving and risk of road crashes among novice and experienced drivers. New England Journal of Medicine 370:54-9. Olson, R.L.; Hanowski, R.J.; Hickman, J.S.; and Bocanegra, J. 2009. Driver distraction in commercial vehicle operations. Report No. FMCSA-RRR-09-242. Washington, DC: Federal Motor Carrier Safety Administration. A 2014 Institute study took a detailed look at cellphone use during entire trips made by 105 drivers whose daily driving was recorded for one year. Farmer, C.M.; Klauer, S.G.; McClafferty, J.A.; and Guo, F. 2014. Relationship of near-crash/crash risk to time spent on a cellphone while driving. Arlington, VA: Insurance Institute for Highway Safety. The quarterly rates of cellphone use were compared with the corresponding quarterly rates of near-crashes and crashes. Higher rates of cellphone use were not associated with higher rates of near-crashes or crashes. 

    Although the risk of a near-crash or crash was 17 percent higher when the driver was interacting with a cellphone, much of this was attributable to reaching for, answering, or dialing a cellphone, which nearly tripled the risk of a near-crash or crash. Most cellphone use consisted of talking or listening, which was not associated with an increased rate of near-crashes or crashes.

    Cellphone use is only one of many sources of distraction that can take drivers’ attention off the road. When not using a phone, drivers more often engage in other behaviors like interacting with passengers, eating, drinking, or smoking, which also can divert attention from the road. Farmer, C.M.; Klauer, S.G.; McClafferty, J.A.; and Guo, F. 2014. Secondary behavior of drivers on cellphones. Arlington, VA: Insurance Institute for Highway Safety. Naturalistic driving studies may not have found an increase in safety-critical events like crashes, near-crashes, traffic conflicts, and lane drifts associated with cellphone use because safety-critical events also may increase when drivers engage in other distractions besides cellphone use.

  5. How many crashes have been caused by drivers using cellphones?

    Based on national data on fatal crashes in the United States, 3,328 people died in crashes in 2012 in which the police reported that distraction was a contributing factor. National Highway Traffic Safety Administration. 2014. Driver electronic device use in 2012. Report no. DOT HS-811-884. Washington, DC: U.S. Department of Transportation. Cellphone use was indicated as a contributing factor in 12 percent of these deaths. However, these statistics are imprecise and likely underestimate the role of distraction in fatal crashes. Police crash reports aren't a reliable way to count cellphone-related collisions because drivers often don't volunteer that they were on the phone and there is usually a lack of other evidence to determine the driver’s phone use. Plus, the codes for reporting distractions on police crash reports vary from state to state.

    In an in-depth study of a nationally representative sample of police-reported crashes occurring during 2005-07 and involving at least one vehicle towed from the scene, crash-involved drivers and witnesses were interviewed at the crash scene to examine the role of driver inattention and other pre-crash factors. Based on these interviews, police reports, and other information, cellphone use (talking, dialing, hanging up or text messaging), was estimated to be a factor in about 3 percent of the crashes. Singh, S. 2010. Distracted driving and driver, roadway, and environmental factors. Report no. DOT HS 811-380. Washington, DC: National Highway Traffic Safety Administration. Although this study attempted to identify pre-crash events, it still is likely that the estimates of distraction are imprecise as they rely heavily on the self-report of drivers and observers.

    Estimates of the crash risk associated with cellphone use have been combined with the estimated prevalence of drivers’ phone use to project the expected number of crashes linked to phone use. An Institute study following this approach indicated that drivers’ phone use could account for 22 percent of all police-reported crashes, based on an estimated fourfold increase in crash risk associated with phone use and survey results indicating that drivers use phones 7 percent of the time. Farmer, C.M.; Braitman, K.A.; and Lund, A.K. 2010. Cellphone use while driving and attributable crash risk. Traffic Injury Prevention 11(5):466-70.  

    However, there is a disconnect between these results and real-world crash trends, which show declines in recent years. There were about 5.6 million police-reported crashes in 2012, considerably fewer than the 6.4 million crashes in 2000, when national observation surveys began documenting the increase in drivers’ phone use. An increase in crashes isn't showing up in insurance claims either. An analysis by HLDI indicates that the rates of insurance collision claims have declined from 2000-2012. Highway Loss Data Institute. 2013. [Unpublished analysis of collision claim frequencies]. Arlington, VA.

  6. Is cellphone use the biggest source of distraction in crashes?

    It’s impossible to gauge the precise contribution of various types of distractions to crashes. Driver distraction was present in crashes long before cellphones came along, but the fact that a driver was distracted around the time of a crash doesn't mean the distraction contributed to the crash. An in-depth study of crashes published in the late 1970s indicated that more than 90 percent of crashes were attributable to driver-related factors; driver inattention was present in 15 percent of the crashes and distraction from something in the vehicle was present in 9 percent. Treat, J.R.; Tumbas, N.S.; McDonald, S.T.;  Shinar, D.; Hume, R.D.; Mayer, R.E.; Stansifer, R.L.; and Castellan, N.J. 1979. Tri-level study of the causes of traffic accidents. Report no. DOT HS 805-099. Washington, DC: National Highway Traffic Safety Administration. More recent research used police crash reports, interviews of witnesses and crash-involved drivers, and other information to study pre-crash factors in crashes occurring in 2005-07. National Highway Traffic Safety Administration. 2008. National motor vehicle crash causation survey: report to congress. Report no. DOT HS-811-059. Washington, DC: U.S. Department of Transportation. Driver-related factors contributed to 93 percent of crashes. Conversing with a passenger was the most common in-vehicle distraction and was present in (and may or may not have contributed to) about 16 percent of crashes. Cellphone use was present in about 3 percent of crashes. Singh, S. 2010. Distracted driving and driver, roadway, and environmental factors. Report no. DOT HS 811-380. Washington, DC: National Highway Traffic Safety Administration.

  7. How do cellphone use and texting affect driving performance?

    The effect of cellphone use on driving performance has been extensively researched. Based on an Institute review of cellphone and driving research, nearly all experimental studies using driving simulators or instrumented vehicles reported that some measures of driver performance were affected by the cognitive distractions associated with cellphone tasks. McCartt, A.T.; Hellinga, L.A.; and Braitman, K.A. 2006. Cell phones and driving: review of research. Traffic Injury Prevention 7(2):89-106. Statistical analyses that aggregated the results of 33 studies in one analysis and 23 studies in another reported significant delays in drivers’ reaction time but small or no effect of cellphone conversations on lane keeping, speed, or following distance. Caird, J.K.; Willness, C.R.; Steel, P.; and Scialfa, C. 2008. A meta-analysis of the effects of cell phones on driver performance. Accident Analysis and Prevention 40(4):1282-93. Horrey, W.J. and Wickens, C.D. 2006. Examining the impact of cell phone conversations on driving using meta-analytic techniques. Human Factors 48(1):196-205.

    Fewer experimental studies have examined texting and driving. Three simulator-based studies found that receiving and sending text messages slowed young drivers’ reaction times and degraded lane-keeping ability. Hosking, S.; Young, K.; and Regan, M. 2006. The effects of text messaging on young novice driver performance. Monash University Accident Research Center. Report no. 246. Melbourne, Victoria: Monash University.
    Reed, N. and Robbins, R. 2008. The effect of text messaging on driver behavior: a simulator study. Published report PPR 367. Berkshire, United Kingdom: Transport Research Laboratory. Drews, F.A.; Yazdani, H.; Godfrey, C.N.; Cooper, J.M.; and Strayer, D.L. 2009. Text messaging during simulated driving. Human Factors 51(5):762-70. Based on a recent review of 14 experimental studies using driving simulators or instrumented vehicles, most studies reported sending or receiving text messages significantly slowed reaction time, increased lane deviations, and increased the length of time drivers looked away from the roadway. Caird, J.K.; Johnston, K.; Willness, C.; and Asbridge, M. 2013. Synthesis of text messaging and driving performance. Proceedings of the Seventh International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design, 348-58. Iowa City, IA: University of Iowa Public Policy Center.

    Cellphone use also affects how drivers scan and process information from the roadway. Drivers generally take their eyes off the roadway to dial or manipulate a hand-held phone. In contrast, drivers engaged in cellphone conversations and other forms of cognitive distraction tend to concentrate their gaze toward the center of the roadway, Recarte, M.A. and Nunes, L.M. 2000. Effects of verbal and spatial-imagery tasks on eye fixations while driving. J. Exp. Psychol. Appl. 6(1):31-43. Recarte, M.A. and Nunes, L.M. 2003. Mental workload while driving: effects on visual search, discrimination, and decision making. J. Exp. Psychol. Appl. 9(2):119-37. Reimer, B.; Mehler, B.; Wang, Y.; and Coughlin, J. F. 2012. A field study on the impact of variations in short-term memory demands on drivers’ visual attention and driving performance across three age groups. Human Factors 54(3):454-68.
    but their attention still may be diverted from driving and interfere with processing what they see. Strayer, D.L.; Drews, F.A.; and Johnston, W.A. 2003. Cell phone-induced failures of visual attention during simulated driving. Journal of Experimental Psychology Applied 9(1):23-32. Using brain imaging techniques, researchers found a 37 percent reduction in brain activity associated with driving when subjects performed a task via a headset while steering a simulated vehicle. Just, M.A.; Keller, T.A.; and Cynkar, J. 2008. A decrease in brain activation with driving when listening to someone speak. Brain Research 1205(2008):70-80. Other researchers have found similar suppression of brain activity associated with visual processing and attention when drivers are cognitively distracted. Bowyer, S.M.; Hsieh L.; Moran, J.E.; Young, R.A.; Manoharan, A.; Liao, C.J.; Yu, Y.; Chiang, Y.; and Tepley, N. 2009. Conversation effects on neural mechanisms underlying reaction time to visual vents while viewing a driving scene using MEG. Brain Research 1251(28):151-61. Strayer, D.L.; Martinez, M.; Cooper, J.M.; and Drews, F.A. 2006. Brain waves suppressed by cell phone conversations. Proceedings of the human Factors and Ergonomics Society 50th Annual Meeting, 2364-7. Santa Monica, CA: Human Factors and Ergonomics Society Consequently, cognitive distractions can lead to so-called “inattention blindness” in which drivers fail to comprehend or process information from objects in the roadway even when they are looking at them. Strayer, D.L.; Drews, F.A.; and Johnston, W.A. 2003. Cell phone-induced failures of visual attention during simulated driving. Journal of Experimental Psychology Applied 9(1):23-32.  

  8. Are hands-free cellphones safer than hand-held cellphones?

    Research on the relative safety of hands-free and hand-held cellphones is mixed. Hands-free phones may eliminate some of the physical and visual distraction of handling phones or dialing, but the cognitive distraction associated with conversation remains. Experimental research using driving simulators indicates that phone conversation tasks, whether using hand-held or hands-free devices, affect some measures of driving performance and increases mental workload relative to just driving. McCartt, A.T.; Hellinga, L.A.; and Braitman, K.A. 2006. Cell phones and driving: review of research. Traffic Injury Prevention 7(2):89-106. Caird, J.K.; Willness, C.R.; Steel, P.; and Scialfa, C. 2008. A meta-analysis of the effects of cell phones on driver performance. Accident Analysis and Prevention 40(4):1282-93. Horrey, W.J. and Wickens, C.D. 2006. Examining the impact of cell phone conversations on driving using meta-analytic techniques. Human Factors 48(1):196-205. Cooper, J.M.; Ingebretsen, H.; and Strayer, D.L. 2014. Mental workload of common voice-based vehicle interactions across six different vehicle systems. Washington, DC: AAA Foundation for Traffic Safety. Strayer, D.L.; Turrill, J.; Coleman, J.;Ortiz, E.V.; and Cooper, J.M. 2014. Measuring cognitive distraction in the automobile II: assessing in-vehicle voice-based interactive technologies. Washington, DC: AAA Foundation for Traffic Safety.

    Two studies of crashes using cellphone billing records to verify phone use found about a fourfold increase in crash risk when conversing on either hands-free or hand-held phones. McEvoy, S.P.; Stevenson, M.R.; McCartt, A.T.; Woodward, M.; Haworth, C.; Palamara, P.; and Cercarelli, R. 2005. Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study. British Medical Journal 331(7514):428-30. Redelmeier, D.A. and Tibshirani, R.J. 1997. Association between cellular-telephone calls and motor vehicle collisions. The New England Journal of Medicine 336:453-58. The studies were unable to estimate crash risk from different types of hands-free devices. They also were unable to determine whether there was any benefit associated with hands-free devices while placing the call. A naturalistic study continuously monitored drivers who reported using their phones while driving every day for one month and examined the risk of a safety-critical event (primarily traffic conflicts and near-crashes) associated with hand-held cellphone use and 2 forms of hands-free cellphone use. Hand-held cellphone use increased the risk of a safety critical event, but hands-free phone use, whether using a portable cellphone or a system built into the vehicle, did not. Fitch, G.A.; Soccolich, S.A.; Guo, F.; McClafferty, J.; Fang, Y.; Olson, R.L.; Perez, M.A.; Hanowski, R.J.; Hankey, J.M.; and Dingus, T.A. 2013. The impact of hand-held and hands-free cell phone use on driving performance and safety-critical event risk. Report no. DOT HS 811-757. Washington, DC: National Highway Traffic Safety Administration.

  9. How common are laws limiting drivers’ use of cellphones?

    Bans on hand-held phone conversations while driving are widespread in other countries and are becoming more common in the U.S. In 2001, New York became the first state to ban hand-held phone conversations by all drivers. Now, 14 states and the District of Columbia have similar laws.

    In 2002, New Jersey became the first state to limit young drivers’ use of any kind of cellphone. Now 37 states and the District of Columbia have similar restrictions. The District of Columbia in 2004 and Connecticut in 2005 prohibited texting while driving as part of a law broadly addressing driver distraction.  In January 2008, Washington became the first state to prohibit texting specifically by all drivers. Now texting is banned for all drivers in 44 states and the District of Columbia, and an additional four states (Mississippi, Missouri, Oklahoma and Texas) prohibit texting only for novice drivers.

    Cellphone laws in the U.S.

  10. Do drivers comply with bans on hand-held phone use and texting?

    Institute research has documented that all-driver bans on hand-held phone conversations can have large and lasting effects on phone use. Based on observations of drivers conducted up to seven years after bans were implemented in New York, the District of Columbia and Connecticut, the rates of driver hand-held cellphone conversations were an estimated 24-76 percent lower than would have been expected without a ban. McCartt, A.T.; Hellinga, L.A.; Strouse, L.M.; and Farmer, C.M. 2010. Long-term effects of handheld cell phone laws on driver handheld cell phone use. Traffic Injury Prevention 11(2):133-41. In the Institute's 2009 telephone survey about cellphone use, 56 percent of drivers in states with bans reported they use phones when driving, compared with 69 percent in states without such laws. Braitman, K.A. and McCartt, A.T. 2010. National reported patterns of driver cellphone use. Traffic Injury Prevention 11(6):543-8. The proportion of drivers who talk on phones and always talk hands-free was 22 percent in states with all-driver bans on hand-held phones and 13 percent in states without all-driver bans.

    Phone bans seem to have less effect on younger drivers. Since Dec. 1, 2006, North Carolina has banned the use of any telecommunications device by drivers younger than 18. Eleven percent of teenagers leaving high schools in the afternoon were using phones prior to the ban, and this did not change significantly when measured five months after the restriction took effect or two years later. Foss, R.D.; Goodwin, A.H.; McCartt, A.T.; and Hellinga, L.A. 2009. Short-term effects of a teenager driver cell phone restriction. Accident Analysis and Prevention 41(3):419-24. Goodwin, A. H.; O’Brien, N.; and Foss, R.D. 2012. Effect of North Carolina’s restriction on teenage driver cell phone use two years after implementation. Accident Analysis and Prevention 48:363-67.

    There is scant information on drivers’ compliance with texting bans. The Institute’s 2009 survey of drivers found that among 18-24 year-olds 45 percent reported texting while driving in states that bar the practice, just shy of the 48 percent of drivers who reported texting in states without bans. Braitman, K.A. and McCartt, A.T. 2010. National reported patterns of driver cellphone use. Traffic Injury Prevention 11(6):543-8. Among drivers ages 25-29, 40 percent reported texting in states with bans, compared with 55 percent in states without bans.

    NHTSA has conducted high-visibility enforcement campaigns in Hartford, Conn., Syracuse, N.Y., the Sacramento Valley Region in California, and in the state of Delaware as a way to increase compliance with cellphone and texting bans. After programs of publicized, high-intensity enforcement of hand-held cellphone and texting bans were implemented, the number of drivers observed holding a phone to their ear declined by 57 percent in Hartford, 32 percent in Syracuse, 34 percent in the Sacramento Valley region, and 33 percent in Delaware. Cosgrove, L.; Chaudhary, N.; and Reagan, I. 2011. Four high-visibility enforcement demonstration waves in Connecticut and New York reduce hand-held phone use. Report No. DOT HS 811-845. Washington, DC: U.S. Department of Transportation. Shick, A.; Vegega, M.; and Chaudhary, N. 2014. Distracted driving high-visibility enforcement demonstrations in California and Delaware. Report no. DOT HS-811-993. Washington, DC: National Highway Traffic Safety Administration. Significant declines also were observed in 3 of the 4 groups of comparison communities where high-visibility enforcement campaigns were not conducted. Observed manipulation of hand-held phones (e.g., dialing, texting) decreased significantly in Syracuse, N.Y. and Hartford, Conn. following the enforcement initiative and did not decrease in the comparison communities.

  11. Do bans on hand-held phone use and texting reduce crashes?

    Despite any effects on phone use and texting, there is little evidence so far that banning hand-held phone use or texting reduces crashes. A 2009 analysis by the Highway Loss Data Institute (HLDI) found that hand-held bans had no effect on insurance collision claim rates. Trempel, R. E.; Kyrychenko, S. Y.; and Moore, M. J. 2011. Does banning hand-held cell phone use while driving reduce collisions? Chance 24(3):6-11. Researchers compared rates of claims for crash damage in three states and the District of Columbia before and after hand-held phone use bans went into effect and found no significant change in claim rates for two jurisdictions relative to comparison states and small, but significant, increases in claim rates in the other two.

    A 2010 HLDI study examined rates of insurance claims filed for damage to vehicles before and after driver texting bans were enacted in four states. Highway Loss Data Institute. 2010. Texting laws and collision claim frequencies. HLDI Bulletin 27(11). Arlington, VA. There was no significant change in one state relative to comparison states and significant increases of 7-9 percent in three states. Increases in claim rates also were found for drivers 25 and younger in these three states.

    The Institute reviewed 11 studies of all-driver hand-held phone bans and texting bans, including the two HLDI studies. McCartt, A.T.; Kidd, D.G.; and Teoh, E.R. 2014. Driver cellphone and texting bans in the United States: evidence of the effectiveness. Annals of Advances in Automotive Medecine 58:99-114. The results were mixed, so it is not clear if laws limiting drivers’ cellphone use are having beneficial effects on crashes. Bans may not have a beneficial effect on crashes even with strong enforcement. Four waves of enforcement campaigns aimed at reducing hand-held cellphone use were conducted in Hartford, Conn. And Syracuse, N.Y during 2010-11. The campaigns reduced observed rates of cellphone conversation and manipulating, but an analysis comparing collision claims in counties with the campaigns to comparison counties without them did not find a corresponding reduction in crashes reported to insurers. Highway Loss Data Institute. 2013. Evaluation of U.S. DOT special enforcement campaigns for hand-held cellphone and texting bans. HLDI Bulletin 30(35). Arlington, VA.

  12. Can technology be used to reduce crash risks related to distracted driving?

    Crash avoidance technology may be the most promising avenue for reducing crash risks related to distractions of any type. This technology can use warnings to redirect a distracted, inattentive, or sleepy driver’s attention back to the roadway if it detects the potential for a collision. Some systems attempt to avoid the collision altogether if a driver does not respond fast enough or does not respond at all.

    More information on crash avoidance technology

    Automakers are integrating "infotainment" systems into vehicles to let drivers and other occupants plug in or wirelessly connect portable electronic devices such as cellphones or MP3 players to vehicle entertainment and communication systems. Some systems allow drivers to interact with portable devices and other vehicle systems using voice commands. Several experimental studies have shown that drivers take shorter glances away from the roadway and keep their eyes on the road for a greater proportion of the time when interacting with a portable device connected to the vehicle using voice commands than they do when using their hands. Ranney, T. A.; Harbluk, J. L.; and Noy, Y. I. 2005. Effects of voice technology on test track driving performance: implications for driver distraction. Human Factors 47(2):439-54. Owens, J. M.; McLaughlin, S.B.; and Sudweeks, J. 2010. On-road comparison of driving performance measures when using handheld and voice-control interfaces for mobile phones and portable music players. Paper No. 2010-01-1036. SAE 2010 World Congress & Exhibition. SAE International: Warrendale, PA. Owens, J. M.; McLaughlin, S. B.; and Sudweeks, J. 2011. Driver performance while text messaging using handheld and in-vehicle systems. Accident Analysis & Prevention 43(3): 939-47. However, using voice commands can be cognitively distracting and can add more steps to a task since voice commands often need to be verified. Reagan, I.J. and Kidd, D.G. 2013. Using heirarchical task analysis to compare four vehicle manufacturers' infotainment systems. Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 1495-2599. Santa Monica, CA: Human Factors and Ergonomics Society. Strayer, D.L.; Cooper, J.M.; Turrill, J.; Coleman, J.; Medeiros-Ward, N.; and Biondi, F. 2013. Measuring cognitive distraction in the automobile. Washington, DC: AAA Foundation for Traffic Safety. The effects of voice-activated integrated systems on crash risk are unknown. NHTSA has issued voluntary guidelines for integrated infotainment systems in an effort to minimize the visual and manual distraction potential of these systems. Office of the Federal Register. 2012. National Highway Traffic Safety Administration. Docket no. NHTSA-2010-0053 - Visual manual NHTSA Driver Distraction Guidelines for in-vehicle electronic devices. Federal Register, vol. 77, no. 80, pp. 24764-66. Washington, DC: National Archives and Records Administration.

    Phone applications that restrict or limit access to electronic devices also have been developed. These apps generally work when vehicles are in motion and can silence the phone, redirect incoming calls to voicemail or respond to text messages with a preprogrammed message. At this point, it is unclear to what extent these apps are used and to what extent they affect drivers’ behavior or crash risk.