Urine ethanol concentration and alcohol hangover severity

BACKGROUND

The aim of this study was to examine the relationship between urine ethanol concentration and alcohol hangover severity.

METHODS

N = 36 healthy social drinkers participated in a naturalistic study, comprising a hangover day and a control day. N = 18 of them have regular hangovers (the hangover group), while the other N = 18 claim to be hangover immune (hangover-immune group). On each test day at 9.30 am, urine samples were collected. Participants rated their overall hangover severity on a scale from 0 (absent) to 10 (extreme), as well as 18 individual hangover symptoms.

RESULTS

Urine ethanol concentration was significantly higher on the hangover day when compared to the control day (p = 0.006). On the hangover day, urine ethanol concentration was significantly lower in the hangover-immune group when compared to the hangover group (p = 0.027). In the hangover-immune group, none of the correlations of urine ethanol concentration with individual hangover symptoms was significant. In contrast, in the hangover group, significant correlations were found with a variety of hangover symptoms, including nausea, concentration problems, sleepiness, weakness, apathy, sweating, stomach pain, thirst, heart racing, anxiety, and sleep problems.

CONCLUSION

Urine ethanol levels are significantly associated with the presence and severity of several hangover symptoms.

In-car usage-based insurance feedback strategies. A comparative driving simulator study

Usage-Based Insurances (UBI) enable policyholders to actively reduce the impact of vehicle insurance costs by adopting a safer and more eco-friendly driving style. UBI is especially relevant for younger drivers, who are a high-risk population. The effectiveness of UBI should be enhanced by providing in-car feedback optimised for individual drivers. Thirty young novice drivers were therefore invited to complete six experimental drives with an in-car interface that provided real-time information on rewards gained, their driving behaviour and the speed limit. Reward size was either displayed directly in euro, indirectly as a relatively large amount of credits, or as a percentage of the maximum available bonus. Also, interfaces were investigated that provided partial information to reduce the potential for driver distraction. Compared to a control no-UBI condition, behaviour improved similarly across interfaces, suggesting that interface personalisation after an initial familiarisation period could be feasible without compromising feedback effectiveness. Practitioner Summary: User experiences and effects on driving behaviour of six in-car interfaces were compared. The interface provided information on driving behaviour and rewards in a UBI setting. Results suggest that some personalisation of interfaces may be an option after an initial familiarisation period as driving behaviour improved similarly across interfaces.

Driving and attention deficit hyperactivity disorder

Adults with attention deficit hyperactivity disorder (ADHD) suffer from various impairments of cognitive, emotional and social functioning, which can have considerable consequences for many areas of daily living. One of those areas is driving a vehicle. Driving is an important activity of everyday life and requires an efficient interplay between multiple cognitive, perceptual, and motor skills. In the present study, a selective review of the literature on driving-related difficulties associated with ADHD is performed, seeking to answer whether individuals with ADHD show increased levels of unsafe driving behaviours, which cognitive (dys)functions of individuals with ADHD are related to driving difficulty, and whether pharmacological treatment significantly improves the driving behaviour of individuals with ADHD. The available research provides convincing evidence that individuals with ADHD have different and more adverse driving outcomes than individuals without the condition. However, it appears that not all individuals with ADHD are affected uniformly. Despite various cognitive functions being related with driving difficulties, these functions do not appear helpful in detecting high risk drivers with ADHD, nor in predicting driving outcomes in individuals with ADHD, since impairments in these functions are defining criteria for the diagnoses of ADHD (e.g., inattention and impulsivity). Pharmacological treatment of ADHD, in particular stimulant drug treatment, appears to be beneficial to the driving difficulties experienced by individuals with ADHD. However, additional research is needed, in particular further studies that address the numerous methodological weaknesses of many of the previous studies.

The use of navigation systems in naturalistic driving

OBJECTIVE

In this study, we assessed the use of portable navigation systems in everyday driving by applying in-vehicle naturalistic driving.

METHOD

Experienced users of navigation systems, 7 females and 14 males, were provided with a specially equipped vehicle for approximately 1 month. Their trips were recorded using 4 cameras, Global Positioning System (GPS) data, and other sensor data. The drivers' navigation system use data were coded from the video recordings, which showed how often and for how long the system was activated and how often and for how long a driver operated the system.

RESULTS

The system was activated for 23% of trips, predominantly on longer and unique trips. Analyses of the percentage of time for which the speed limit was exceeded showed no evidence of differences between trips for which the navigation system was used or not used. On trips for which the navigation system was activated, participants spent about 5% of trip time interacting with the device. About 40% of interacting behavior took place in the first 10% of the trip time, and about 35% took place while the car was standing still or moving at a very low speed; that is, 0-10 km/h.

CONCLUSION

These results shed light on how and when drivers use navigation systems. They suggest that although drivers regulate their use of such systems to some extent, they often perform risky tasks while driving.

The impact of immediate or delayed feedback on driving behaviour in a simulated Pay-As-You-Drive system

Pay-As-You-Drive (PAYD) insurance links an individual's driving behaviour to the insurance fee that they pay, making car insurance more actuarially accurate. The best known PAYD insurance format is purely mileage based and is estimated to reduce accidents by about 15% (Litman, 2011). However, these benefits could be further enhanced by incorporating a wider range of driving behaviours, such as lateral and longitudinal accelerations and speeding behaviour, thereby stimulating not only a safe but also an eco-friendly driving style. Currently, feedback on rewards and driver behaviour is mostly provided through a web-based interface, which is presented temporally separated from driving. However, providing immediate feedback within the vehicle itself could elicit more effect. To investigate this hypothesis, two groups of 20 participants drove with a behavioural based PAYD system in a driving simulator and were provided with either delayed feedback through a website, or immediate feedback through an in-car interface, allowing them to earn up to €6 extra. To be clear, every participant in the web group did actually view their feedback during the one week between sessions. Results indicate clear driving behaviour improvements for both PAYD groups as compared to baseline rides and an equal sized control group. After both PAYD groups had received feedback, the initial advantage of the in-car group was reduced substantially. Taken together with usability ratings and driving behaviours in specific situations these results show a moderate advantage of using immediate in-car feedback. However, the study also showed that under conditions of feedback certainty, the effectiveness of delayed feedback approaches that of immediate feedback as compared to a naïve control group.

In search of a standard for assessing the crash risk of driving under the influence of drugs other than alcohol; results of a questionnaire survey among researchers

OBJECTIVE

To find a gold standard for crash risk assessment studies in the field of driving under the influence of psychoactive substances.

METHODS

A questionnaire survey on methodological aspects concerning study designs was sent to researchers in the field of driving under the influence of psychoactive substances. The questionnaire was aimed at the 4 main study designs to assess the crash risk of driving under the influence: case-control studies, culpability studies, pharmaco-epidemiological studies, and experimental studies.

RESULTS

The response rate for the questionnaire was 68 percent (N = 57). Forty-six percent of the respondents had a preference for assessing the crash risk by means of case-control studies, 35 percent by means of experimental studies, 14 percent by means of culpability studies, and 5 percent by means of pharmaco-epidemiological studies. In practice, however, only 51 percent of the researchers actually used the study type they preferred in theory. For the 4 most commonly used study designs, similarity rates varied from 66 to 81 percent for the theoretically preferred design and from 52 to 77 percent for the design that was actually applied.

CONCLUSIONS

Based on the results of the questionnaire survey, it can be concluded that despite several attempts in the past to standardize study design, there is still no common standard for assessing the crash risk of driving under the influence. The differences are not only caused by practical, legal, financial, or ethical issues but also by differences between researchers concerning their theoretically preferred study design.

Mobile phone use while cycling: incidence and effects on behaviour and safety

The effects of mobile phone use on cycling behaviour were studied. In study 1, the prevalence of mobile phone use while cycling was assessed. In Groningen 2.2% of cyclists were observed talking on their phone and 0.6% were text messaging or entering a phone number. In study 2, accident-involved cyclists responded to a questionnaire. Only 0.5% stated that they were using their phone at the time of the accident. In study 3, participants used a phone while cycling. The content of the conversation was manipulated and participants also had to enter a text message. Data were compared with just cycling and cycling while listening to music. Telephoning coincided with reduced speed, reduced peripheral vision performance and increased risk and mental effort ratings. Text messaging had the largest negative impact on cycling performance. Higher mental workload and lower speed may account for the relatively low number of people calling involved in accidents. STATEMENT OF RELEVANCE: Although perhaps mainly restricted to flat countries with a large proportion of cyclists, mobile phone use while cycling has increased and may be a threat to traffic safety, similar to phone use while driving a car. In this study, the extent of the problem was assessed by observing the proportion of cyclists using mobile phones, sending questionnaires to accident-involved cyclists and an experimental study was conducted on the effects of mobile phone use while cycling.