The association between handheld phone bans and the prevalence of handheld phone conversations among young drivers in the United States

Demographic characteristics and trends of cell phone use while driving citations in selected states in the United States, 2010-2020

OBJECTIVE

Distracted driving is a leading cause of motor vehicle crashes, and cell phone use is a major source of in-vehicle distraction. Many states in the United States have enacted cell phone use laws to regulate drivers' cell phone use behavior to enhance traffic safety. Numerous studies have examined the effects of such laws on drivers' cell phone use behavior based on self-reported and roadside observational data. However, little was known about who actually violated the laws at the enforcement level. This study sought to uncover the demographic characteristics of drivers cited for cell phone use while driving and whether these characteristics changed over time since the enactment of cell phone laws.

METHODS

We acquired useable traffic citation data for 7 states in the United States from 2010 to 2020 and performed descriptive and regression analyses.

RESULTS

Male drivers were cited more for cell phone use while driving. Handheld and texting bans were associated with a greater proportion of cited drivers aged 40 and above, compared to texting-only bans. Trends in the citations issued based on drivers' age group following the enactment of different cell phone laws were also uncovered. The proportion of citations issued to drivers aged 60 and above increased over time but the temporal trend remained insignificant when population effect was considered.

CONCLUSIONS

This study examined the demographic characteristics of drivers cited for cell phone use while driving in selected states with texting-only bans or handheld and texting bans. The results reveal policy-based differences in trends in the proportion of citations issued to drivers in different age groups.

The association between strengthened cellphone laws and police-reported rear-end crash rates

INTRODUCTION

Prior evaluations of the connection between cellphone bans and crashes show unclear results. California, Oregon, and Washington enacted legislation (effective in 2017) to update earlier bans specific to handheld conversation and texting. This study evaluated the relationship between the laws and rear-end rates, a crash type sensitive to visual-manual cellphone use, in California, Oregon, and Washington.

METHOD

Negative binomial regression compared the change in monthly per capita rear-end crash rates in California, Oregon, and Washington before and after the law changes relative to two control states, Colorado and Idaho, during 2015-2019. Analyses examined (a) rear-end crashes with injuries in all three study states, including minor to fatal injuries; and (b) rear-end crashes of all severities in California and Washington, including property-damage-only crashes and crashes with injuries; Oregon was excluded from this analysis because of a 2018 change to its reporting criteria for property-damage-only crashes.

RESULTS

Washington's strengthened law was associated with a significant 7.6% reduction in the rate of monthly rear-end crashes of all severities relative to the controls. Law changes in Oregon and Washington were associated with significant reductions of 8.8% and 10.9%, respectively, in the rates of monthly rear-end crashes with injury relative to the controls. California did not experience changes in rear-end crash rates of all severities or with injuries associated with the strengthened law.

CONCLUSION

The results of this study are mixed, with law changes associated with significant reductions in rear-end crash rates in two of the three study states. Differences in the wording of the laws, levels of enforcement, and sanction severity may help explain the divergent results.

PRACTICAL APPLICATION

Crash reductions in Oregon and Washington suggest that enacting legislation that comprehensively bans practically all visual-manual cellphone activity may have made the laws easier to enforce and clarified to drivers that handheld cellphone use is unacceptable in these states.

Short-term impacts of all-driver handheld cellphone bans on high-schoolers' texting while driving: quasi-experimental analyses of Illinois and Georgia

Teen drivers are more likely than their older counterparts to engage in distracted driving. Many states prohibit cellphone use for teen drivers, but only prohibit texting for all drivers. Evidence that these laws have been effective is mixed. We hypothesize that recent policy changes in Georgia and Illinois from teen cellphone bans with all-driver texting bans to all-driver handheld phone bans yielded short-term reductions in teen texting while driving. We analyzed Youth Risk Behavior Surveys in Georgia, Illinois, and control states North Carolina and Michigan. We estimated the reduction in texting while driving associated with policy changes via difference-in-differences models. In Illinois, 45.4 % of high school drivers texted while driving in 2013. After a 2014 policy change to an all-driver handheld ban, the percentage decreased in 2015 to 41.8 %, and decreased further in 2017 to 37.7 %. The adjusted DID estimate comparing Illinois to Michigan from 2013 to 2017 was -8.3 % (95 % CI: -15.5 % 1.1 %; p-value = 0.025). In Georgia, the percentage decreased from 37.5 % before the law to 30.8 % after, and the adjusted DID estimate comparing Georgia to North Carolina was -10.8 % (95 % CI: -19.0 %, -2.5 %; p-value = 0.011) than in North Carolina. Results support all-driver handheld phone bans to improve traffic safety for high school drivers.

The impact of Illinois' comprehensive handheld phone ban on talking on handheld and handsfree cellphones while driving

INTRODUCTION

Distracted driving has been linked to multiple driving decrements and is responsible for thousands of motor-vehicle fatalities annually. Most U.S. states have enacted restrictions on cellphone use while driving, the strictest of which prohibit any manual operation of a cellphone while driving. Illinois enacted such a law in 2014. To better understand how this law affected cellphone behaviors while driving, associations between Illinois' handheld phone ban and self-reported talking on handheld, handsfree, and any cellphone (handheld or handsfree) while driving were estimated.

METHODS

Data from annual administrations of the Traffic Safety Culture Index from 2012-2017 in Illinois and a set of control states were leveraged. The data were cast into a difference-in-differences (DID) modeling framework, which compared Illinois to control states in terms of pre- to post-intervention changes in the proportion of drivers who self-reported the three outcomes. Separate models for each outcome were fit, and additional models were fit to the subset of drivers who talk on cellphones while driving.

RESULTS

In Illinois, the pre- to post-intervention decrease in the drivers' probability of self-reporting talking on a handheld phone was significantly more extreme than that of drivers in control states (DID estimate -0.22; 95% CI -0.31, -0.13). Among drivers who talk on cellphones while driving, those in Illinois exhibited a more extreme increase in the probability of talking on a handsfree phone while driving than those control states (DID estimate 0.13; 95% CI 0.03, 0.23).

CONCLUSIONS

These results suggest that Illinois' handheld phone ban reduced talking on handheld phones while driving among study participants. They also corroborate the hypothesis that the ban promoted substitution from handheld to handsfree phones among drivers who talk on the phone while driving.

PRACTICAL APPLICATIONS

These findings should encourage other states to enact comprehensive handheld phone bans to improve traffic safety.

Talking on hands-free and handheld cellphones while driving in association with handheld phone bans

INTRODUCTION

Concurrent use of a cellphone while driving impairs driving abilities, and studies of policy effectiveness in reducing distracted driving have yielded mixed results. Furthermore, few studies have considered how hands-free phone use associates with handheld phone bans. It is not clear whether hand-held phone bans dissuade some drivers from using the phone while driving completely, or whether it simply promotes a shift to hands-free use. The present study estimates the association between handheld phone policies and self-reported talking on hands-free and handheld cellphones while driving.

METHODS

Our data consisted of 16,067 respondents to annual administrations of the Traffic Safety Culture Index from 2012-2017. Our primary exposure variable was handheld phone policy, and our primary outcome variables were self-reported talking on any phone, self-reported talking on a handheld phone, and self-reported talking on a hands-free phone while driving. We estimated adjusted prevalence ratios of the outcomes associated with handheld phone bans via modified Poisson regression.

RESULTS

Drivers in states with handheld bans were 13% less likely to self-report talking on any type of cellphone (handheld or hands-free) while driving. When broken down by cellphone type, drivers in states with handheld bans were 38% less likely to self-report talking on a handheld phone and 10% more likely to self-report talking on a hands-free phone while driving.

CONCLUSIONS

Handheld phone bans were associated with more self-reported talking on hands-free phones and less talking on handheld phones, consistent with a substitution hypothesis. Handheld bans were also associated with less talking on any phone while driving, supporting a net safety benefit.

PRACTICAL APPLICATIONS

In the absence of a national ban on handheld phone use while driving, our study supports state handheld phone bans to deter distracted driving and improve traffic safety.

Examining driver distraction in the context of driving speed: An observational study using disruptive technology and naturalistic data

Considering the number of people who have been involved in crashes associated with driver distractions, it is important to understand the characteristics of distracted driving on public roadways. While experiments have indicated that driver distractions are associated with slower driving speeds, the methodologies tend to have limited external validity. Observational studies are often conducted under limited circumstances - be it time or location. Therefore, in order to better understand the nature of driver distractions, the authors investigated the relationships between driving speed, posted speed limits, and phone handling frequency through naturalistic driving data obtained (via disruptive technology) from 8,240 mobile application users on state-maintained highways throughout Texas. As a measure of manual distractions, a phone handling rate (PHR; times/hours driven) was calculated based on phone rotations. Within-subject comparisons were drawn for driving speed and posted speed limits under normal driving conditions and distracted conditions. The analysis revealed a strong negative correlation between PHR and driving speed (r_s = -0.87). Paired t-tests revealed significantly lower driving speeds (p = 0.000 < 0.01, d = -0.48, η = 0.69) and posted speed limits (p = 0.000 < 0.01, d = -0.20, η = 0.42) during phone handling events when compared to driving without phone handling. On average, users drove 3.26 mph slower in distracted conditions than in undistracted conditions. Driving speed had a larger effect size than posted speed limits. The findings were in line with existing theories and experiments as well as other observational studies conducted at fixed locations. Although this research did not reveal causal relations, it is noteworthy that speed reduction with manual distractions was observed under real road conditions. Spatial analyses are recommended to conduct in order to paint a more thorough picture of speed reduction, its relationship to space, and crash risks related to distracted driving.

Support for distracted driving laws: An analysis of adolescent drivers from the Traffic Safety Culture Index from 2011 to 2017

INTRODUCTION

Adolescent drivers are often the focus of traffic safety legislation as they are at increased risk for crash-related injury and death. However, the degree to which adolescents support distracted driving laws and factors contributing to their support are relatively unknown. Using a large, nationally weighted sample of adolescent drivers in the United States, we assessed if perceived threat from other road users' engagement in distracted driving, personal engagement in distracted driving behaviors, and the presence of state distracted driving laws was associated with support for distracted driving laws.

METHODS

The sample included 3565 adolescents (aged 16-18) who participated in the Traffic Safety Culture Index survey from 2011 to 2017. A modified Poisson regression model with robust errors was fit to the weighted data to examine support for distracted driving laws. Models included age, gender, year, state distracted driving laws, personal engagement in distracted driving behavior, and perceived threat from other road users' engaging in distracted driving.

RESULTS

Approximately 87% of adolescents supported a law against texting and emailing compared to 66% who supported a universal handheld cellphone law. Support for distracted driving legislation was associated with greater perceived threat of other road users engaging in distracted driving while accounting for personal engagement in distracted driving, state distracted driving laws, and developmental covariates.

DISCUSSION

Greater understanding of the factors behind legislative support is needed. Public health interventions focused on effectively translating the risks of cellphone use while driving and effective policy will further improve the traffic safety culture.

Cellphone laws and teens' calling while driving: analysis of repeated cross-sectional surveys in 2013, 2015, 2017, and 2019

Background

Distracted driving among teens is a public health and safety concern. Most states in the U.S. have sought to restrict cellphone use while driving by enacting laws. This study examines the difference in prevalence of self-reported calling while driving (CWD) between states with different cellphone bans.

Methods

Demographics and CWD data were extracted from state Youth Risk Behavior Surveys (YRBS) from 14 states in 2013, 2015, 2017, and 2019. The state YRBS is conducted every 2 years with a representative sample of 9th through 12th grade students attending public school. States were grouped by type of cellphone law(s): no ban (the absence of both handheld calling ban and young driver ban), young driver ban (a ban on all forms of cellphone use while driving, for young drivers only), or concurrent ban (a young driver ban plus a ban on handheld calling for all drivers irrespective of age). Poisson regression models with robust variance were used to estimate prevalence ratios comparing CWD prevalence across ban types.

Results

In total, 157,423 high school students participated in the surveys, and 65,044 (45%) participants reached the minimum age to obtain an intermediate license and drove during the 30 days prior the survey. Approximately 53% of participants reported CWD at least once during the previous 30 days, and the percentages varied widely by states (range: 51–55%). Compared to students from states with no ban, those from states with concurrent bans were 19%(95% CI: 14–24%) less likely to engage in CWD. Students in states with concurrent bans were 23% less likely to engage in CWD compared to students in states with young driver bans (95% CI:17–27%).

Conclusions

Engaging in CWD is common among teen drivers. The concurrent implementation of a handheld calling ban and a young driver ban was associated with a lower prevalence of CWD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40621-020-00290-x.

Validation of not-at-fault driver representativeness assumption for quasi-induced exposure using U.S. national traffic databases

INTRODUCTION

The quasi-induced exposure (QIE) method has been widely implemented into traffic safety research. One of the key assumptions of QIE method is that not-at-fault drivers represent the driving population at the time of a crash. Recent studies have validated the QIE representative assumption using not-at-fault drivers from three-or-more vehicle crashes (excluding the first not-at-fault drivers; D3_other) as the reference group in single state crash databases. However, it is unclear if the QIE representativeness assumption is valid on a national scale and is a representative sample of driving population in the United States. The aims of this study were to assess the QIE representativeness assumption on a national scale and to evaluate if D3_other could serve as a representative sample of the U.S. driving population.

METHOD

Using the Fatality Analysis Reporting System (FARS) and the National Occupant Protection Use Survey (NOPUS), distributions of driver gender, age, vehicle type, time, and roadway type among the not-at-fault drivers in clean two-vehicle crashes, the first not-at-fault drivers in three-or-more-vehicle crashes, and the remaining not-at-fault drivers in three-or-more vehicle crashes were compared to the driver population observed in NOPUS.

RESULTS

The results showed that with respect to driver gender, vehicle type, time, and roadway type, drivers among D3_other did not show statistical significant difference from NOPUS observations. The age distribution of D3_other driver was not practically different to NOPUS observations.

CONCLUSIONS

Overall, we conclude that D3_other drivers in FARS represents the driving population at the time of the crash. Practical applications: Our study provides a solid foundation for future studies to utilize D3_other as the reference group to validate the QIE representativeness assumption and has potential to increase the generalizability of future FARS studies.

Texting-While-Driving Bans and Motor Vehicle Crash-Related Emergency Department Visits in 16 US States: 2007-2014

OBJECTIVES

To examine the impact of state texting bans on motor vehicle crash (MVC)-related emergency department (ED) visits.

METHODS

We used ED data from 16 US states between 2007 and 2014. We employed a difference-in-difference approach and conditional Poisson regressions to estimate changes in counts of MVC-related ED visits in states with and without texting bans. We also constructed age cohorts to explore whether texting bans have differential impacts by age group.

RESULTS

On average, states with a texting ban saw a 4% reduction in MVC-related ED visits (incidence rate ratio = 0.96; 95% confidence interval = 0.96, 0.97). This equates to an average of 1632 traffic-related ED visits prevented per year in states with a ban. Both primary and secondary bans were associated with significant reductions in MVC-related visits to the ED regardless of whether they were on all drivers or young drivers only. Individuals aged 64 years and younger in states with a texting ban saw significantly fewer MVC-related ED visits following its implementation.

CONCLUSIONS

Our findings suggest that states' efforts to curb distracted driving through texting bans and decrease its negative consequences are associated with significant decreases in the incidence of ED visits that follow an MVC.

Association between cellphone use while driving legislation and self-reported behaviour among adult drivers in USA: a cross-sectional study

OBJECTIVES

Cellphone use behaviours can vary demographically in the USA. This study examined whether legislation restricting cellphone use while driving was associated with lower self-reported hand-held cellphone conversations or texting behaviours among adult drivers of different ages (19-24, 25-39, 40-59,≥60 years), sex, race/ethnicity (white non-Hispanic, black non-Hispanic, Hispanic, Other) or rurality (urban, rural).

DESIGN

Cross-sectional study.

SETTING

USA.

PARTICIPANTS

Individuals ≥19 years of age who indicated they were a current driver and participated in the 2011-2014 Traffic Safety Culture Index Surveys (n=9706).

PRIMARY OUTCOME

The exposure was the presence of a hand-held calling or texting ban applicable to all drivers (ie, universal) at time of survey. Modified Poisson regression with robust SE was used to estimate the risk of engaging in these self-reported behaviours.

RESULTS

In fully adjusted models, universal texting bans were not associated with lower texting behaviours (adjusted risk ratio [aRR]=0.92; 95% CI 0.84, 1.01). In stratified, fully adjusted models, men and those of other racial/ethnic origin were 13% and 33% less likely, respectively (aRR=0.87; 95% CI 0.77, 0.98; aRR=0.67; 95% CI 0.46, 0.97), to engage in texting behaviours if a universal texting ban was effective in their state. Conversely, universal hand-held calling bans were associated with lower self-reported hand-held cellphone conversations across every sub-group. In fully adjusted models, the presence of a hand-held calling ban was associated with 40% lower (aRR=0.60, 95% CI 0.54, 0.67) self-reported hand-held cellphone conversations while driving.

CONCLUSIONS

Universal hand-held calling bans were associated with lower self-reported cellphone conversations for adult drivers. More interventional work targeting adult drivers may be needed to reduce texting while driving.

Cellphone Legislation and Self-Reported Behaviors Among Subgroups of Adolescent U.S. Drivers

PURPOSE

The relationship between cellphone use while driving legislation and self-reported adolescent driver behavior is poorly understood, especially across demographic subgroups. This study investigated the relationship between statewide cellphone legislation and cellphone use behaviors across adolescent driver subgroups, including age (16/17 vs. 18), sex, race/ethnicity (white non-Hispanic and others), and rurality (urban or rural).

METHODS

Data from the 2011-2014 Traffic Safety Culture Index Surveys were combined with state legislation. The outcomes were self-reported texting and handheld cellphone conversations. The exposure was the presence of a texting or handheld cellphone ban applicable to all drivers (i.e., universal) in the drivers' state of residence. A multilevel, modified Poisson regression model was used to estimate the risk of engaging in these behaviors.

RESULTS

Approximately 34% of respondents reported to have driven while conversing, and 37% texted and drove in the 30 days before the survey. Universal handheld calling bans were associated with lower occurrences of cellphone conversations across all groups except rural drivers. Overall, handheld cellphone bans were associated with 55% lower (adjusted risk ratio .45, 95% confidence interval .32-.63) occurrences of cellphone conversations. However, universal texting bans were not associated with fewer texting behaviors in any subgroup.

CONCLUSIONS

Universal handheld calling bans may discourage adolescents from engaging in handheld phone conversations, whereas universal texting bans may not fully discourage texting behaviors. More interventional or educational work is necessary, particularly addressing texting while driving.