Association between cellular-telephone calls and motor vehicle collisions

Transient effects of transfusion and feeding advances (volumetric and caloric) on necrotizing enterocolitis development: A case-crossover study

Objective

To evaluate the short-term effects of feed fortification, feed volume increase, and PRBC transfusion on the odds of developing NEC.

Study design

Case-crossover study of neonatal intensive care infants born at ≤ 32 weeks’ gestation who were admitted to 5 central Ohio intensive care units from January 2012-July 2016 and developed NEC Bell Stage ≥2. Each patient served as their own control, with exposure during the 48-hour period just prior to NEC onset (hazard period) being compared to a preceding 48-hour control period, thus eliminating confounding by patient factors fixed between both intervals. NEC onset was determined by chart review as the earliest occurrence of one of the following within 24 hours of confirmatory x-ray: (1) antibiotic initiation, (2) enteral feeding cessation, (3) physician first notified of abdominal concerns, or (4) abdominal x-ray ordered. Conditional logistic regression compared exposures to feed volume increase, fortification, and PRBC transfusion during the 48-hour period prior to NEC onset to those during a preceding 48-hour control period. Analyses were stratified by gestational age and anemia (defined: hemoglobin ≤ 9.3 g/dL within 7 days of NEC onset).

Results

We included 63 infants with confirmed NEC. Acute exposure to fortification (odds ratio [OR]: 1.67, 95% confidence interval [CI]: 0.61, 4.59), feed volume increase (OR: 0.63, 95% CI: 0.28, 1.38), and PRBC transfusion (OR: 1.80, 95% CI: 0.60, 5.37) was not associated with the onset of NEC. Gestational age and anemia did not significantly modify the associations. Sensitivity testing substituting 24- and 72-hour hazard and control periods produced similar results.

Conclusion

Using a case-crossover design, we did not detect an association between NEC development and feed fortification, feed volume increase, or PRBC transfusion within 48-hours prior to NEC-onset. Replication in a larger set of cases is needed.

Distraction-related road traffic collisions

OBJECTIVES

We aimed to prospectively study distraction-related road traffic collision injuries, their contributory factors, severity, and outcome.

METHODS

Data were prospectively collected on all hospitalized road traffic collision trauma patients in Al-Ain City who were drivers at the collision time over one and half years. Driver's inattentive behaviors preceding the collision were collected by interviewing the admitted drivers.

RESULTS

There were 444 drivers, 330 of them were fully oriented patients, out of them only 44 (13%) were distracted. Nineteen (5.8%) drivers were distracted by using mobile phones, 12 (3.6%) were pre-occupied with deep thinking, six (1.8%) were talking with other passengers, four (1.2%) were picking things in the vehicle, and three (0.9%) were using entertainment systems. The maximum distraction occurred during the time of 6 am - 12 noon when the traffic was crowded. There were no significant differences between distracted and non-distracted drivers in demographical and physiological factors, injured regions, and outcomes.

CONCLUSION

Distraction of alert drivers causes 13% of road traffic collisions in Al-Ain city. About 40 percent of the distracted drivers involved in road traffic collisions (RTC) were using mobile phones. Our study supports the ban of use of cell phones while driving.

What's the law got to do with it? Legislation regarding in-vehicle technology use and its impact on driver distraction

Legislation in the road transport domain aims to control safety on the roads. Despite this, a critical issue affecting road safety is that of driver distraction. Although poorly defined, distraction is a significant road safety issue which, in part, is caused by the prevalence of technology within vehicles. Legislation surrounding the use of in-vehicle technologies are explored in this paper from a socio-technical system perspective. This reveals the wider context of the road transport system operating under the current laws using an Accimap analysis. A distinction in the law between the use of hand-held mobile phones, a device that is typically banned for use by drivers worldwide, and the use of other technological devices that are covered by more general laws against 'careless' and/or 'dangerous' driving was found. Historically, individual drivers' have been blamed for distraction, whereas the systems approach shows how current legislation may have created the conditions necessary for driver distraction.

Improving our understanding of multi-tasking in healthcare: Drawing together the cognitive psychology and healthcare literature

Multi-tasking is an important skill for clinical work which has received limited research attention. Its impacts on clinical work are poorly understood. In contrast, there is substantial multi-tasking research in cognitive psychology, driver distraction, and human-computer interaction. This review synthesises evidence of the extent and impacts of multi-tasking on efficiency and task performance from health and non-healthcare literature, to compare and contrast approaches, identify implications for clinical work, and to develop an evidence-informed framework for guiding the measurement of multi-tasking in future healthcare studies. The results showed healthcare studies using direct observation have focused on descriptive studies to quantify concurrent multi-tasking and its frequency in different contexts, with limited study of impact. In comparison, non-healthcare studies have applied predominantly experimental and simulation designs, focusing on interleaved and concurrent multi-tasking, and testing theories of the mechanisms by which multi-tasking impacts task efficiency and performance. We propose a framework to guide the measurement of multi-tasking in clinical settings that draws together lessons from these siloed research efforts.

Relationship between family history of alcohol addiction, parents' education level, and smartphone problem use scale scores

Background and aims Smartphones are ubiquitous. As smartphones increased in popularity, researchers realized that people were becoming dependent on their smartphones. The purpose here was to provide a better understanding of the factors related to problematic smartphone use (PSPU). Methods The participants were 100 undergraduates (25 males, 75 females) whose ages ranged from 18 to 23 (mean age = 20 years). The participants completed questionnaires to assess gender, ethnicity, year in college, father's education level, mother's education level, family income, age, family history of alcoholism, and PSPU. The Family Tree Questionnaire assessed family history of alcoholism. The Mobile Phone Problem Use Scale (MPPUS) and the Adapted Cell Phone Addiction Test (ACPAT) were used to determine the degree of PSPU. Whereas the MPPUS measures tolerance, escape from other problems, withdrawal, craving, and negative life consequences, the ACPAT measures preoccupation (salience), excessive use, neglecting work, anticipation, lack of control, and neglecting social life. Results Family history of alcoholism and father's education level together explained 26% of the variance in the MPPUS scores and 25% of the variance in the ACPAT scores. The inclusion of mother's education level, ethnicity, family income, age, year in college, and gender did not significantly increase the proportion of variance explained for either MPPUS or ACPAT scores. Discussion and conclusions Family history of alcoholism and father's education level are good predictors of PSPU. As 74%-75% of the variance in PSPU scale scores was not explained, future studies should aim to explain this variance.

Self-controlled designs in pharmacoepidemiology involving electronic healthcare databases: a systematic review

Background

Observational studies are widely used in pharmacoepidemiology. Several designs can be used, in particular self-controlled designs (case-crossover and self-controlled case series). These designs offer the advantage of controlling for time-invariant confounders, which may not be collected in electronic healthcare databases. They are particularly useful in pharmacoepidemiology involving healthcare database. To be valid, they require the presence of some characteristics (key validity assumptions), and in such situations, these designs should be preferred. We aimed at describing the appropriate use and reporting of the key validity assumptions in self-controlled design studies.

Methods

Articles published between January 2011 and December 2014, and describing a self-controlled study design involving electronic healthcare databases were retrieved. The appropriate use (fulfilment of key assumptions) was studied in terms of major (abrupt onset event, rare or recurrent event, and intermittent exposure) and minor assumptions (those for which the design can be adapted).

Results

Among the 107 articles describing a self-controlled design, 35/53 (66%) case-crossover studies, and 48/55 (87%) self-controlled case series fulfilled the major validity assumptions for use of the design; 4/35 and 14/48 respectively did not fulfill the minor assumptions. Overall, 31/53 (58%) case-crossover studies and 34/55 (62%) self-controlled case series fulfilled both major and minor assumptions. The reporting of the methodology or the results was appropriate, except for power calculation.

Conclusions

Self-controlled designs were not appropriately used in34% and 13% of the articles we reviewed that described a case-crossover or a self-controlled case series design, respectively. We encourage better use of these designs in situations in which major validity assumptions are fulfilled (i.e., for which they are recommended), accounting for situations for which the design can be adapted.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-016-0278-0) contains supplementary material, which is available to authorized users.

Constructing a publically available distracted driving database and research tool

BACKGROUND

The goal of the current work was to create a publicly available visualization tool of distracted driving research, the purpose of which is to allow the public and other stakeholders to empirically inform questions of their choice that may bear on policy discussions.

METHODS

Fifty years of distracted driving research was used to design a comprehensive database of studies that evaluated the effects of distraction on driving performance. Distraction sources (e.g., texting, talking, visual distraction) and performance measures were defined, and the sample of studies were evaluated and categorized by their measures.

RESULTS

The final product yielded 342 studies using various methodologies. Across all measures, 1297 found distractions degraded driving performance, 54 found distraction improved driving performance, and 257 found distraction had no effect on driving performance. An analysis of the most common phone distractions (texting and talking) showed that texting almost always results in degraded performance. Aggregate data reveal no difference in performance decrements for hand-held or hands-free phones even though single studies of those variables vary in their outcomes.

CONCLUSIONS

This project illustrates how scientific research can be made publically available for use by a diverse audience of stakeholders. An important result of this project is that data aggregated along a simple set of characteristics such as whether or not performance is decreased, improved or not affected, can reveal trends in the data that are less clear from any individual study.

Advanced driver assistance systems: Using multimodal redundant warnings to enhance road safety

This study investigated whether multimodal redundant warnings presented by advanced assistance systems reduce brake response times. Warnings presented by assistance systems are designed to assist drivers by informing them that evasive driving maneuvers are needed in order to avoid a potential accident. If these warnings are poorly designed, they may distract drivers, slow their responses, and reduce road safety. In two experiments, participants drove a simulated vehicle equipped with a forward collision avoidance system. Auditory, vibrotactile, and multimodal warnings were presented when the time to collision was shorter than five seconds. The effects of these warnings were investigated with participants performing a concurrent cell phone conversation (Exp. 1) or driving in high-density traffic (Exp. 2). Braking times and subjective workload were measured. Multimodal redundant warnings elicited faster braking reaction times. These warnings were found to be effective even when talking on a cell phone (Exp. 1) or driving in dense traffic (Exp. 2). Multimodal warnings produced higher ratings of urgency, but ratings of frustration did not increase compared to other warnings. Findings obtained in these two experiments are important given that faster braking responses may reduce the potential for a collision.

Design and Evaluation of Shape-Changing Haptic Interfaces for Pedestrian Navigation Assistance

Shape-changing interfaces are a category of device capable of altering their form in order to facilitate communication of information. In this work, we present a shape-changing device that has been designed for navigation assistance. 'The Animotus' (previously, 'The Haptic Sandwich' ), resembles a cube with an articulated upper half that is able to rotate and extend (translate) relative to the bottom half, which is fixed in the user's grasp. This rotation and extension, generally felt via the user's fingers, is used to represent heading and proximity to navigational targets. The device is intended to provide an alternative to screen or audio based interfaces for visually impaired, hearing impaired, deafblind, and sighted pedestrians. The motivation and design of the haptic device is presented, followed by the results of a navigation experiment that aimed to determine the role of each device DOF, in terms of facilitating guidance. An additional device, 'The Haptic Taco', which modulated its volume in response to target proximity (negating directional feedback), was also compared. Results indicate that while the heading (rotational) DOF benefited motion efficiency, the proximity (translational) DOF benefited velocity. Combination of the two DOF improved overall performance. The volumetric Taco performed comparably to the Animotus' extension DOF.

Outcomes of road traffic injuries before and after the implementation of a camera ticketing system: a retrospective study from a large trauma center in Saudi Arabia

BACKGROUND

Road traffic injuries (RTIs) are the third leading cause of death in Saudi Arabia. Because speed is a major risk factor for severe crash-related injuries, a camera ticketing system was implemented countrywide in mid-2010 by the traffic police in an effort to improve traffic safety. There are no published studies on the effects of the system in Saudi Arabia.

OBJECTIVE

To examine injury severity and associated mortality at a large trauma center before and after the implementation of the ticketing system.

DESIGN

Retrospective, analytical.

SETTING

Trauma center of a tertiary care center in Riyadh.

PATIENTS AND METHODS

The study included all trauma registry patients seen in the emergency department for a crash-related injury (automobile occupants, pedestrians, or motorcyclists) between January 2005 and December 2014. Associations with outcome measures were assessed by univariate and multivariate methods.

MAIN OUTCOME MEASURE(S)

Injury severity score (ISS), Glasgow coma scale (GCS) and mortality.

RESULTS

The study included all trauma registry patients seen in the emergency department for a crash-related injury. All health outcomes improved in the period following implementation of the ticketing system. Following implementation, ISS scores decreased (-3.1, 95% CI -4.6, -1.6) and GCS increased (0.47, 95% CI 0.08, 0.87) after adjusting for other covariates. The odds of death were 46% lower following implementation than before implementation. When the data were log-transformed to account for skewed data distributions, the results remained statistically significant.

CONCLUSIONS

This study suggests positive health implications following the implementation of the camera ticketing system. Further investment in public health interventions is warranted to reduce preventable RTIs.

LIMITATIONS

The study findings represent a trauma center at a single hospital in Riyadh, which may not generalize to the Saudi population.

Cell-phone use diminishes self-awareness of impaired driving

Multitasking diminishes the self-awareness of performance that is often essential for self-regulation and self-knowledge. Participants drove in a simulator while either talking or not talking on a hands-free cell phone. Following previous research, participants who talked on a cell phone made more serious driving errors than control participants who did not use a phone while driving. Control participants' assessments of the safeness of their driving and general ability to drive safely while distracted were negatively correlated with the actual number of errors made when they were driving. By contrast, cell-phone participants' assessments of the safeness of their driving and confidence in their driving abilities were uncorrelated with their actual errors. Thus, talking on a cell phone not only diminished the safeness of participants' driving, it diminished their awareness of the safeness of their driving.

Hands-Free versus Hand-Held Cell Phone Conversation on a Braking Response by Young Drivers

As some states allow motorists to use hands-free cell phones only while driving, this study was done to examine some braking responses to see if conversing on these two types of cell phones affects quick responding. College-age drivers ( n = 25) completed reaction time trials in go/no-go situations under three conditions: control (no cell phone or conversation), and conversing on hands-free and hand-held cell phones. Their task involved moving the right foot from one pedal to another as quickly as possible in response to a visual signal in a lab setting. Significantly slower reaction times, movement times, and total response times were found for both cell phone conditions than for the control but no differences between hands-free and hand-held phone conditions. These findings provide additional support that talking on cell phones, regardless if it is hands-free or hand-held, reduces speed of information processing.

Multi-modal demands of a smartphone used to place calls and enter addresses during highway driving relative to two embedded systems

There is limited research on trade-offs in demand between manual and voice interfaces of embedded and portable technologies. Mehler et al. identified differences in driving performance, visual engagement and workload between two contrasting embedded vehicle system designs (Chevrolet MyLink and Volvo Sensus). The current study extends this work by comparing these embedded systems with a smartphone (Samsung Galaxy S4). None of the voice interfaces eliminated visual demand. Relative to placing calls manually, both embedded voice interfaces resulted in less eyes-off-road time than the smartphone. Errors were most frequent when calling contacts using the smartphone. The smartphone and MyLink allowed addresses to be entered using compound voice commands resulting in shorter eyes-off-road time compared with the menu-based Sensus but with many more errors. Driving performance and physiological measures indicated increased demand when performing secondary tasks relative to 'just driving', but were not significantly different between the smartphone and embedded systems. Practitioner Summary: The findings show that embedded system and portable device voice interfaces place fewer visual demands on the driver than manual interfaces, but they also underscore how differences in system designs can significantly affect not only the demands placed on drivers, but also the successful completion of tasks.

When Can I Drive After Orthopaedic Surgery? A Systematic Review

BACKGROUND

Patients often ask their doctors when they can safely return to driving after orthopaedic injuries and procedures, but the data regarding this topic are diverse and sometimes conflicting. Some studies provide observer-reported outcome measures, such as brake response time or simulators, to estimate when patients can safely resume driving after surgery, and patient survey data describing when patients report a return to driving, but they do not all agree. We performed a systematic review and quality appraisal for available data regarding when patients are safe to resume driving after common orthopaedic surgeries and injuries affecting the ability to drive.

QUESTIONS/PURPOSES

Based on the available evidence, we sought to determine when patients can safely return to driving after (1) lower extremity orthopaedic surgery and injuries; (2) upper extremity orthopaedic surgery and injuries; and (3) spine surgery.

METHODS

A search was performed using PubMed and EMBASE^®, with a list of 20 common orthopaedic procedures and the words "driving" and "brake". Selection criteria included any article that evaluated driver safety or time to driving after major orthopaedic surgery or immobilization using observer-reported outcome measures or survey data. A total of 446 articles were identified from the initial search, 48 of which met inclusion criteria; abstract-only publications and non-English-language articles were not included. The evidence base includes data for driving safety on foot, ankle, spine, and leg injuries, knee and shoulder arthroscopy, hip and knee arthroplasty, carpal tunnel surgery, and extremity immobilization. Thirty-four of the articles used observer-reported outcome measures such as total brake time, brake response time, driving simulator, and standardized driving track results, whereas the remaining 14 used survey data.

RESULTS

Observer-reported outcome measures of total brake time, brake response time, and brake force postoperatively suggested patients reached presurgical norms 4 weeks after right-sided procedures such as TKA, THA, and ACL reconstruction and approximately 1 week after left-sided TKA and THA. The collected survey data suggest patients resumed driving 1 month after right-sided and left-sided TKAs. Patients who had THA reported returning to driving between 6 days and 3 months postoperatively. Observer-reported outcome measures showed that patients' driving abilities often are impaired when wearing an immobilizing cast above or below the elbow or a shoulder sling on their dominant arm. Patients reported a return to driving on average 2 months after rotator cuff repair procedures and approximately 1-3 months postoperatively for total shoulder arthroplasties. Most patients with spine surgery had normal brake response times at the time of hospital discharge. Patients reported driving 6 weeks after total disc arthroplasty and anterior cervical discectomy and fusion procedures.

CONCLUSIONS

The available evidence provides a best-case scenario for when patients can return to driving. It is important for observer-reported outcome measures to have normalized before a patient can consider driving, but other factors such as strength, ROM, and use of opioid analgesics need to be considered. This review can provide a guideline for when physicians can begin to consider evaluating these other factors and discussing a return to driving with patients. Survey data suggest that patients are returning to driving before observer-reported outcome measures have normalized, indicating that physicians should tell patients to wait longer before driving. Further research is needed to correlate observer-reported outcome measures with adverse events, such as motor vehicle accidents, and clinical tests that can be performed in the office.

LEVEL OF EVIDENCE

Level III, therapeutic study.

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

PURPOSE

Fourteen US states and the District of Columbia have banned handheld phone use for all drivers. We examined whether such legislation was associated with reduced handheld phone conversations among drivers aged younger than 25 years.

METHODS

Data from the 2008 to 2013 National Occupant Protection Use Survey were merged with states' legislation. The outcome was roadside-observed handheld phone conversation at stop signs or lights. Logistic regression was used.

RESULTS

A total of 32,784 young drivers were observed. Relative to drivers who were observed in states without a universal handheld phone ban, the adjusted odds ratio of phone conversation was 0.42 (95% confidence interval, 0.33-0.53) for drivers who were observed in states with bans. The relative reduction in phone conversation was 46% (23%, 61%) for laws that were effective less than 1 year, 55% (32%, 70%) for 1-2 years, 63% (51%, 72%) for 2 years or more, relative to no laws.

CONCLUSIONS

Universal handheld phone bans may be effective at reducing handheld phone use among young drivers.

Driving and Multitasking: The Good, the Bad, and the Dangerous

Previous research has shown that multitasking can have a positive or a negative influence on driving performance. The aim of this study was to determine how the interaction between driving circumstances and cognitive requirements of secondary tasks affect a driver's ability to control a car. We created a driving simulator paradigm where participants had to perform one of two scenarios: one with no traffic in the driver's lane, and one with substantial traffic in both lanes, some of which had to be overtaken. Four different secondary task conditions were combined with these driving scenarios. In both driving scenarios, using a tablet resulted in the worst, most dangerous, performance, while passively listening to the radio or answering questions for a radio quiz led to the best driving performance. Interestingly, driving as a single task did not produce better performance than driving in combination with one of the radio tasks, and even tended to be slightly worse. These results suggest that drivers switch to internally focused secondary tasks when nothing else is available during monotonous or repetitive driving environments. This mind wandering potentially has a stronger interference effect with driving than non-visual secondary tasks.

Cognitive Workload while Driving and Talking on a Cellular Phone or to a Passenger

Twelve adults experienced in using cellular telephones participated in an investigation of driving and performing a communication task. They navigated a closed serpentine driving course, requiring constant driving activity. Their communication task was responding to a verbal cognitive test battery administered by the passenger or via cellular telephone. The test battery consisted of sentence remembering with read-back and verbal puzzle solving. Baseline treatments were navigating the course without communication and responding to the test battery while parked. Subjects were prompted to report their current level of workload, using the Subjective Workload Assessment Technique (SWAT), throughout their tasks. Driving speeds were significantly lower when using the phone than they were with the passenger speaking, but the analysis did not reveal a difference in perceived workload between these conditions. Workload ratings were lower in the drive-only condition than they were when the driver used the phone.

The Effect of Hands-Free Cellular Telephone Conversation Complexity on Choice Response Time in a Detection Task

This paper presents the results of a study addressing the effect of hands-free cellular phone conversation complexity on choice response time in a detection task. The study utilized an open-loop simulation technique to study four different levels of the secondary task of using a hands-free cellular telephone and their effect on the primary task of responding to stimuli presented through a driving scene. Results from the study showed that the inclusion of the secondary task had a significant effect on choice response time. Also, choice response time associated with complex conversations involving visual scanning was found to be significantly different from that when the phone was not used. The implications of the use of hands-free phones are also discussed.

In-Vehicle Cell Phones: Fatal Distraction—Yes or No?

Debate in the popular press regarding the issue of cell phone use on American roadways is extremely prevalent, highly vituperative, and almost completely devoid of actual hard data on the problem itself. Editorials are rife with emotionally-charged personal accounts of tragedies or near-tragedies, but suspiciously empty of any facts regarding the issues involved or experimental evidence supporting the positions they adopt. The resulting general consensus in the public mind is that these products are a dangerous national problem and that something must be done about them. The rash of legislation proposing various types of quick fix is proof that lawmakers are being crowded into a position that something must be done about this “problem”, though the real data surrounding this issue is mixed at best.

This paper attempts to place the problem in its proper perspective using publicly available facts and figures in an attempt to support an alternative solution.

Passenger and Cell-Phone Conversations in Simulated Driving

Previous work on use of cell phones while driving compared cell phone conversations while driving with driving only conditions. This study investigated how conversing on a cell phone differs from conversing with a passenger. Participants conversed about close-call situations they experienced. We compared how well drivers followed task instructions when driving only, when driving and conversing on a cell phone, and when driving and conversing with a passenger. The results show that the number of driving errors was highest in the cell-phone condition. Analyzing the conversations we found that in passenger conversations more references were made to traffic and more turn taking followed those references than in cell phone conversations. The results show that passenger conversations differ from cell phone conversations because the surrounding traffic becomes a topic of the conversation, helping driver and passenger to share situation awareness, and mitigating the potential effects of conversation on driving.

What do Drivers Fail to See When Conversing on a Cell Phone?

Our research examined the effects of hands-free cell phone conversations on simulated driving. We found that even when participants looked directly at objects in the driving environment, they were less likely to create a durable memory of those objects if they were conversing on a cell phone. Moreover, this pattern was obtained for objects of both high- and low-relevance, suggesting that very little semantic analysis of the objects occurs outside the restricted focus of attention. These data support the inattention-blindness interpretation in which the disruptive effects of cell phone conversations on driving are due in large part to the diversion of attention from driving to the phone conversation. We suggest that even when participants are directing their gaze at objects in the driving environment that they may fail to “see” them when they are on the phone because attention is directed elsewhere.

Effects of Age and Auditory and Visual Dual-Tasks on Closed Road Driving Performance

The aim of this study was to understand how visual and auditory dual tasks impact upon the driving behavior of young and old participants. The effect of a secondary task on measures of driving performance including the recognition of road signs, detection and avoidance of large low contrast road hazards, judgment of cone gaps, and time to complete the course was assessed for young and older participants as they drove around a 5 km closed road driving course. The secondary task required participants to verbally report the sums of pairs of numbers presented either through a computer speaker (auditorially) or via a dashboard mounted monitor (visually) while driving. The results show that drivers reported fewer road signs, increased their time to complete the road course, and misjudged cone gaps more frequently under the dual-task (visual and auditory) conditions compared to the single task condition and these effects were greater for the older participants.

Driving Safety

Driving is a common and hazardous activity that is a prominent cause of death worldwide. Driver behavior represents a predominant cause, contributing to over 90% of crashes. In this review, I will focus on how driver behavior influences driving safety by describing the types of crashes and their general causes, the driving process, the perceptual and cognitive characteristics of drivers, and driver types and impairments. Evidence from each of these perspectives suggests that breakdowns of a multilevel control process are the fundamental factors that undermine driving safety. Drivers adapt and drive safely in a broad range of situations but fail when expectations are violated or when feedback is inadequate. The review concludes by considering driving safety from a societal risk management perspective.

Examining driver behavior at the onset of yellow in a traffic simulator environment: Comparisons between random parameters and latent class logit models

This study involves an examination of driver behavior at the onset of a yellow signal indication. Behavioral data were obtained from a driving simulator study that was conducted through the National Advanced Driving Simulator (NADS) laboratory at the University of Iowa. These data were drawn from a series of events during which study participants drove through a series of intersections where the traffic signals changed from the green to yellow phase. The resulting dataset provides potential insights into how driver behavior is affected by distracted driving through an experimental design that alternated handheld, headset, and hands-free cell phone use with "normal" baseline driving events. The results of the study show that male drivers ages 18-45 were more likely to stop. Participants were also more likely to stop as they became more familiar with the simulator environment. Cell phone use was found to some influence on driver behavior in this setting, though the effects varied significantly across individuals. The study also demonstrates two methodological approaches for dealing with unobserved heterogeneity across drivers. These include random parameters and latent class logit models, each of which analyze the data as a panel. The results show each method to provide significantly better fit than a pooled, fixed parameter model. Differences in terms of the context of these two approaches are discussed, providing important insights as to the differences between these modeling frameworks.

Do German drivers use their smartphones safely?-Not really!

Research in the laboratory as well as in naturalistic driving studies has shown that texting while driving seems to be the most dangerous driver distraction. However, there is still some discussion about the extent to which drivers adapt their behavior to the traffic situation. Accordingly, they might use their phones only in easy driving situations but refrain from doing so when driving becomes more demanding. For Germany, no reliable data on these topics could be found although overall smartphone use has also increased exponentially in this country. As observational studies have proven to be an effective means to gather these data, such a study was done observing 11,837 drivers in three big German cities (Braunschweig, Hannover, Berlin) during daytime. An alarmingly high rate of texting while driving was found (4.5%) as compared to other international studies. This was even more frequent than the use of handheld (2.2%) and hands-free (1.7%) phones combined. Thus, there seems to be a special problem in Germany with texting which should be further examined as this activity is highly distracting. Finally, there was some indication that drivers adapt their secondary task activities to the requirements of the driving task (e.g. somewhat less texting when moving than when stationary at a red traffic light). However, these adaptations were not very strong. Thus, drivers seem to underestimate the dangers due to distraction. This could be a starting point for countermeasures which increase this awareness of danger.

Decisions and actions of distracted drivers at the onset of yellow lights

Driving on an approach to a signalized intersection while distracted is relatively risky, as potential vehicular conflicts and resulting angle collisions tend to be relatively more severe compared to other locations. Given the prevalence and importance of this particular scenario, the objective of this study was to examine the decisions and actions of distracted drivers during the onset of yellow lights. Driving simulator data were obtained from a sample of 69 drivers under baseline and handheld cell phone conditions at the University of Iowa - National Advanced Driving Simulator. Explanatory variables included age, gender, cell phone use, distance to stop-line, and speed. Although there is extensive research on drivers' responses to yellow traffic signals, the examinations have been conducted from a traditional regression-based approach, which do not necessary provide the underlying relations and patterns among the sampled data. In this paper, we exploit the benefits of both classical statistical inference and data mining techniques to identify the a priori relationships among main effects, non-linearities, and interaction effects. Results suggest that the probability of yellow light running increases with the increase in driving speed at the onset of yellow. Both young (18-25 years) and middle-aged (30-45 years) drivers reveal reduced propensity for yellow light running whilst distracted across the entire speed range, exhibiting possible risk compensation during this critical driving situation. The propensity for yellow light running for both distracted male and female older (50-60 years) drivers is significantly higher. Driver experience captured by age interacts with distraction, resulting in their combined effect having slower physiological response and being distracted particularly risky.

Disentangling the influence of cell phone usage in the dilemma zone: An econometric approach

This paper focuses on developing an analysis framework to study the impact of cell phone treatment (cell phone type and call status) on driver behavior in the presence of a dilemma zone. Specifically, we examine how the treatment influences the driver maneuver decision at the intersection (stop or cross) and the eventual success of the maneuver. For a stop maneuver, success is defined as stopping before the stop line. Similarly, for a cross maneuver, success is defined as clearing the intersection safely before the light turns red. The eventual success or failure of the driver's decision process is dependent on the factors that affected the maneuver decision. Hence it is important to recognize the interconnectedness of the stop or cross decision with its eventual success (or failure). Toward this end, we formulate and estimate a joint framework to analyze the stop/cross decision with its eventual success (or failure) simultaneously. The study is conducted based on driving simulator data provided online for the 2014 Transportation Research Board Data Contest at http://depts.washington.edu/hfsm/upload.php. The model is estimated to analyze drivers' behavior at the onset of yellow by employing exogenous variables from three broad categories: driver characteristics, cell phone attributes and driving attributes. We also generate probability surfaces to identify dilemma zone distribution associated with different cell phone treatment types. The plots clearly illustrate the impact of various cellphone treatments on driver dilemma zone behavior.

Road traffic accidents and self-reported Portuguese car driver's attitudes, behaviors, and opinions: Are they related?

OBJECTIVE

This study aims to characterize Portuguese car drivers in terms of demographic characteristics, driving experience, and attitudes, opinions, and behaviors concerning road traffic safety. Furthermore, associations between these characteristics and self-reported involvement in a road traffic accident as a driver in the last 3 years were analyzed. A final goal was to develop a final predictive model of the risk of suffering a road traffic accident.

METHODS

A cross-sectional analytic study was developed, based on a convenience sample of 612 car drivers. A questionnaire was applied by trained interviewers, embracing various topics related to road safety such as driving under the influence of alcohol or drugs, phone use while driving, speeding, use of advanced driver assistance systems, and the transport infrastructure and environment (European Project SARTRE 4, Portuguese version). From the 52 initial questions, 19 variables were selected through principal component analysis. Then, and in addition to the usual descriptive measures, logistic binary regression models were used in order to describe associations and to develop a predictive model of being involved in a road traffic accident.

RESULTS

Of the 612 car drivers, 37.3% (228) reported being involved in a road traffic accident with damage or injury in the past 3 years. In this group, the majority were male, older than 65, with no children, not employed, and living in an urban area. In the multivariate model, several factors were identified: being widowed (vs. single; odds ratio [OR] = 3.478, 95% confidence interval [95% CI], 1.159-10.434); living in a suburban area (vs. a rural area; OR = 5.023, 95% CI, 2.260-11.166); having been checked for alcohol once in the last 3 years (vs. not checked; OR = 3.124, 95% CI, 2.040-4,783); and seldom drinking an energetic beverage such as coffee when tired (vs. always do; OR = 6.822, 95% CI, 2.619-17.769) all suffered a higher risk of being involved in a car accident.

CONCLUSIONS

The results obtained with regard to behavioral factors meet the majority of the risk factors associated with car accidents referred to in the literature. This study highlights the relation of relatively minor accidents (the majority with no injuries) with an urban (or semi-urban) context and involving older drivers. These accidents are not usually the focus of road safety literature (mainly death and serious health loss) but, in addition to the economic costs involved, they can have a huge impact on road safety (e.g., pedestrian). Specifically, the following interventions can be proposed: more detailed clinical examinations to identify real competencies to drive especially in older drivers (active aging can constitute a new challenge in road safety and new paradigms can arise) and education campaigns on how to cope with fatigue. Future studies in large samples and not based on self-reported behaviors should be developed.

Why Do Drivers Use Mobile Phones While Driving? The Contribution of Compensatory Beliefs

The current study is the first to investigate the contribution of compensatory beliefs (i.e., the belief that the negative effects of an unsafe behavior can be "neutralized" by engaging in another safe behavior; e.g., "I can use a mobile phone now because I will slow down ") on drivers’ mobile phone use while driving. The effects of drivers’ personal characteristics on compensatory beliefs, mobile phone use and self-regulatory behaviors were also examined. A series of questions were administered to drivers, which included (1) personal measures, (2) scales that measured compensatory beliefs generally in substance use and with regard to driving safety, and (3) questions to measure drivers’ previous primary mobile phone usage and corresponding self-regulatory actions. Overall, drivers reported a low likelihood of compensatory beliefs, prior mobile phone use, and a strong frequency of self-regulatory behaviors. Respondents who had a higher tendency toward compensatory beliefs reported more incidents or crash involvement caused by making or answering calls and sending or reading messages. The findings provide strong support for the contribution of compensatory beliefs in predicting mobile phone usage in the context of driving. Compensatory beliefs can explain 41% and 43% of the variance in the active activities of making calls and texting/sending messages compared with 18% and 31% of the variance in the passive activities of answering calls and reading messages. Among the regression models for predicting self-regulatory behaviors at the tactical or operational level, compensatory beliefs emerge as significant predictors only in predicting shorter conversations while on a call. The findings and limitations of the current study are discussed.

The role of self-regulation in the context of driver distraction: A simulator study

OBJECTIVE

There is considerable evidence for the negative effects of driver distraction on road safety. In many experimental studies, drivers have been primarily viewed as passive receivers of distraction. Thus, there is a lack of research on the mediating role of their self-regulatory behavior. The aim of the current study was to compare drivers' performance when engaged in a system-paced secondary task with a self-paced version of this task and how both differed from baseline driving performance without distraction.

METHODS

Thirty-nine participants drove in a simulator while performing a secondary visual-manual task. One group of drivers had to work on this task in predefined situations under time pressure, whereas the other group was free to decide when to work on the secondary task (self-regulation group). Drivers' performance (e.g., lateral and longitudinal control, brake reaction times) was also compared with a baseline condition without any secondary task.

RESULTS

For the system-paced secondary task, distraction was associated with high decrements in driving performance (especially in keeping the lateral position). No effects were found for the number of collisions, probably because of the lower driving speeds while distracted (compensatory behavior). For the self-regulation group, only small impairments in driving performance were found. Drivers engaged less in the secondary task during foreseeable demanding or critical driving situations.

CONCLUSIONS

Overall, drivers in the self-regulation group were able to anticipate the demands of different traffic situations and to adapt their engagement in the secondary task, so that only small impairments in driving performance occurred. Because in real traffic drivers are mostly free to decide when to engage in secondary tasks, it can be concluded that self-regulation should be considered in driver distraction research to ensure ecological validity.

Injury prevention programs against distracted driving: Are they effective?

INTRODUCTION

Distracted driving (talking and/or texting) is a growing public safety problem, with increasing incidence among adult drivers. The aim of this study was to identify the incidence of distracted driving (DD) among health care providers and to create awareness against DD. We hypothesized that distracted driving is prevalent among health care providers and a preventive campaign against distracted driving would effectively decrease distracted driving among health care providers.

METHODS

We performed a 4-phase prospective interventional study of all health care providers at our level 1 trauma center. Phase 1: one week of pre-intervention observation; phase 2: one week of intervention; phase 3: one week of postintervention observation; and phase 4: one week of 6 months of postintervention observation. Observations were performed outside employee parking garage at the following time intervals: 6:30-8:30 a.m., 4:40-5:30 p.m., and 6:30-7:30 p.m. Intervention included an e-mail survey, pamphlets and banners in the hospital cafeteria, and a postintervention survey. Hospital employees were identified with badges and scrubs, employees exiting through employee gate, and parking pass on the car. Outcome measure was incidence of DD pre, post, and 6 months postintervention.

RESULTS

A total of 15,416 observations (pre: 6,639, post: 4,220, 6 months post: 4,557) and 520 survey responses were collected. The incident of DD was 11.8% among health care providers. There was a significant reduction in DD in each time interval of observation between pre- and postintervention. On subanalysis, there was a significant decrease in talking (P = .0001) and texting (P = .01) while driving postintervention compared to pre-intervention. In the survey, 35.5% of respondents admitted to DD and 4.5% respondents were involved in an accident due to DD. We found that 77% respondents felt more informed after the survey and 91% respondents supported a state legislation against DD. The reduction in the incidence of DD postintervention was sustained even at 6-month follow-up.

CONCLUSION

There was a 32% reduction in the incidence of distracted driving postintervention, which remained low even at 6-month follow-up. Implementation of an effective injury prevention campaign could reduce the incidence of distracted driving nationally.

Why drivers use cell phones and support legislation to restrict this practice

The use of cell phones while driving is ubiquitous, particularly in countries where the practice is legal. However, surveys indicate that most drivers favor legislation to limit the use of mobile devices during the operation of a vehicle. A study was conducted to understand this inconsistency between what drivers do and what they advocate for others. Participants completed a survey about their driving attitudes, abilities, and behaviors. Following previous research, drivers reported using cell phones for benefits such as getting work done. The hypocrisy of using cell phones while advocating restrictions appears to stem from differences in the perceived safety risks of self vs. others' use of cell phones. Many if not most drivers believe they can drive safely while using mobile devices. However, they lack confidence in others' ability to drive safely while distracted and believe that others' use of cell phones is dangerous. The threat to public safety of others' usage of mobile devices was one of the strongest independent predictors of support for legislation to restrict cell phone use.

Cell-Phone–Induced Driver Distraction

Our research examined the effects of hands-free cell-phone conversations on simulated driving. We found that even when participants looked directly at objects in the driving environment, they were less likely to create a durable memory of those objects if they were conversing on a cell phone. This pattern was obtained for objects of both high and low relevance, suggesting that very little semantic analysis of the objects occurs outside the restricted focus of attention. Moreover, in-vehicle conversations do not interfere with driving as much as cell-phone conversations do, because drivers are better able to synchronize the processing demands of driving with in-vehicle conversations than with cell-phone conversations. Together, these data support an inattention-blindness interpretation wherein the disruptive effects of cell-phone conversations on driving are due in large part to the diversion of attention from driving to the phone conversation.

Student motorcyclists' mobile phone use while driving in Vientiane, Laos

To investigate mobile phone use while driving among student motorcyclists in Laos, we conducted a school-based questionnaire survey in central Vientiane in May 2014. Of the 883 high school students who reported to drive motorcycles at least once a week, 40% have ever used phones while driving motorcycles in both sexes. Those phone users had longer driving exposures than non-users, with about half engaging in phone use while driving at least 2 days a week and 70% engaging for 1 min or longer on an average day. They reported not just talking on the phone while driving but operating the phone such as dialling and text-messaging. In some instances, phone use was reportedly involved in their past crash experiences. To formulate a sound policy on this emerging distracting behaviour among motorcyclists, its contribution to the occurrence of overall crashes among motorcyclists should be investigated.

Safety-critical event risk associated with cell phone tasks as measured in naturalistic driving studies: A systematic review and meta-analysis

A systematic review and meta-analysis of naturalistic driving studies involving estimates of safety-critical event risk associated with handheld device use while driving is described. Fifty-seven studies identified from targeted databases, journals and websites were reviewed in depth, and six were ultimately included. These six studies, published between 2006 and 2014, encompass seven sets of naturalistic driver data and describe original research that utilized naturalistic methods to assess the effects of distracting behaviors. Four studies involved non-commercial drivers of light vehicles and two studies involved commercial drivers of trucks and buses. Odds ratios quantifying safety-critical event (SCE) risk associated with talking, dialing, locating or answering, and texting or browsing were extracted. Stratified meta-analysis of pooled odds ratios was used to estimate SCE risk by distraction type; meta-regression was used to test for sources of heterogeneity. The results indicate that tasks that require drivers to take their eyes off the road, such as dialing, locating a phone and texting, increase SCE risk to a greater extent than tasks that do not require eyes off the road such as talking. Although talking on a handheld device did not increase SCE risk, further research is required to determine whether it indirectly influences SCE risk (e.g., by encouraging other cell phone activities). In addition, a number of study biases and quality issues of naturalistic driving studies are discussed.

SPIDER: A Framework for Understanding Driver Distraction

OBJECTIVE

The objective was to identify key cognitive processes that are impaired when drivers divert attention from driving.

BACKGROUND

Driver distraction is increasingly recognized as a significant source of injuries and fatalities on the roadway.

METHOD/RESULTS

A "SPIDER" model is developed that identifies key cognitive processes that are impaired when drivers divert attention from driving. SPIDER is an acronym standing for scanning, predicting, identifying, decision making, and executing a response.

CONCLUSION

When drivers engage in secondary activities unrelated to the task of driving, SPIDER-related processes are impaired, situation awareness is degraded, and the ability to safely operate a motor vehicle may be compromised.

APPLICATION

The pattern of interference helps to illuminate the sources of driver distraction and may help guide the integration of new technology into the automobile.

Modernization of the Driver Behaviour Questionnaire

INTRODUCTION

The current study builds on previous versions of the Driver Behaviour Questionnaire (DBQ) by incorporating a larger sample of driving behaviors targeting inattention, distraction, aggressive driving, and health related to aging. The goals of this study were to determine if the resulting factor structure was consistent with a more contemporary view of unsafe driving behaviors, and to determine whether scores on the factors could predict self-reported collisions and police citations.

METHODS

The instrument was given to a sample of 3295 drivers ranging in age from 19 to 80+ years old. It was divided in two sections, the first to provide demographic information and driving history data and the second containing 105 driver behavior questions.

RESULTS

An exploratory factor analysis resulted in a 65-item scale organized in four factors. The factors were labeled tentatively as Inattention Errors, Age-Related Problems, Distraction and Hurry, and Aggressive Violations. Regression analyses showed that the factors were predictors of self-reported, at-fault collisions and police citations.

PRACTICAL IMPLICATIONS

The factor scores found in this research are consistent with a useful theoretical framework for understanding unsafe driver actions, and demonstrate some potential to identify several individual difference variables that predict self-reported collisions and citations.

Judging Thieves of Attention: Commentary on "Assessing Cognitive Distraction in the Automobile," by Strayer, Turrill, Cooper, Coleman, Medeiros-Ward, and Biondi (2015)

The laudable effort by Strayer and his colleagues to derive a systematic method to assess forms of cognitive distraction in the automobile is beset by the problem of nonstationary in driver response capacity. At the level of the overall goal of driving, this problem conflates actual on-road behavior; characterized by underspecified task satisficing, with our own understandable, scientifically inspired aspiration for measuring deterministic performance optimization. Measures of response conceived under this latter imperative are, at best, only shadowy reflections of the actual phenomenological experience involved in real-world vehicle control. Whether we, as a research community, can resolve this issue remains uncertain. However, we believe we can mount a positive attack on what is arguably another equally important dimension of the collision problem.

Driver Compensation: Impairment or Improvement?

Strayer et al.'s conclusion that their "cognitive distraction scale" for auditory-vocal tasks indicates "significant impairments to driving" is not supported by their data. Additional analysis demonstrates that slower brake reaction times during auditory-vocal tasks were fully compensated for by longer following distances to the lead car. Naturalistic driving data demonstrate that cellular conversation decreases crash risk, the opposite of the article's assumption. Hence, the scale's internal and external validities for indicating driving impairment are highly questionable.

Driven to Distraction

We address several themes that emerged in the commentaries related to our target article. First, we consider the relationship between cognitive distraction and crash risk. Second, we discuss the development of our cognitive distraction scale. Third, we weigh issues of self-regulation, appropriate baselines, and satisficing. Finally, we identify several areas where additional research is needed to refine our understanding of driver distraction and crash risk.

Real-world effects of using a phone while driving on lateral and longitudinal control of vehicles

INTRODUCTION

Technologies able to augment human communication, such as smartphones, are increasingly present during all daily activities. Their use while driving, in particular, is of great potential concern, because of the high risk that distraction poses during this activity. Current countermeasures to distraction from phone use are considerably different across countries and not always widely accepted/adopted by the drivers.

METHODS

This study utilized naturalistic driving data collected from 108 drivers in the Integrated Vehicle-Based Safety Systems (IVBSS) program in 2009 and 2010 to assess the extent to which using a phone changes lateral or longitudinal control of a vehicle. The IVBSS study included drivers from three age groups: 20–30 (younger), 40–50 (middle-aged), and 60–70 (older).

RESULTS

Results from this study show that younger drivers are more likely to use a phone while driving than older and middle-aged drivers. Furthermore, younger drivers exhibited smaller safety margins while using a phone. Nevertheless, younger drivers did not experience more severe lateral/longitudinal threats than older and middle-aged drivers, probably because of faster reaction times. While manipulating the phone (i.e., dialing, texting), drivers exhibited larger lateral safety margins and experienced less severe lateral threats than while conversing on the phone. Finally, longitudinal threats were more critical soon after phone interaction, suggesting that drivers terminate phone interactions when driving becomes more demanding.

CONCLUSIONS

These findings suggest that drivers are aware of the potential negative effect of phone use on their safety. This awareness guides their decision to engage/disengage in phone use and to increase safety margins (self-regulation). This compensatory behavior may be a natural countermeasure to distraction that is hard to measure in controlled studies. Practical Applications: Intelligent systems able to amplify this natural compensatory behavior may become a widely accepted/adopted countermeasure to the potential distraction from phone operation while driving.

Assessing Cognitive Distraction in the Automobile

OBJECTIVE

The objective was to establish a systematic framework for measuring and understanding cognitive distraction in the automobile.

BACKGROUND

Driver distraction from secondary in-vehicle activities is increasingly recognized as a significant source of injuries and fatalities on the roadway.

METHOD

Across three studies, participants completed eight in-vehicle tasks commonly performed by the driver of an automobile. Primary, secondary, subjective, and physiological measures were collected and integrated into a cognitive distraction scale.

RESULTS

In-vehicle activities, such as listening to the radio or an audio book, were associated with a low level of cognitive workload; the conversation activities of talking to a passenger in the vehicle or conversing with a friend on a handheld or hands-free cell phone were associated with a moderate level of cognitive workload; and using a speech-to-text interfaced e-mail system involved a high level of cognitive workload.

CONCLUSION

The research established that there are significant impairments to driving that stem from the diversion of attention from the task of operating a motor vehicle and that the impairments to driving are directly related to the cognitive workload of these in-vehicle activities. Moreover, the adoption of voice-based systems in the vehicle may have unintended consequences that adversely affect traffic safety.

APPLICATION

These findings can be used to help inform scientifically based policies on driver distraction, particularly as they relate to cognitive distraction stemming from the diversion of attention to other concurrent activities in the vehicle.

On the Effects of Listening and Talking to Humans and Devices on Driving

The body of research on cognitive distraction while driving is vast and spans many decades. To this research, the authors of the target article add three experiments that measure a number of cognitive tasks across laboratory, simulation, and on-road contexts. The pattern of decrements is similar across contexts, when expressed as an index, and when compared to previous research. Measurement, task, and generalizability issues arise from the approaches taken by the authors. For example, the use of "pure" cognitive tasks may not necessarily generalize to everyday driving behavior, wherein visual and physical distractions are inherently interleaved with cognitive tasks. A valuable contribution of the authors' future research on cognitive distractions would be to predict relative crash risk.