Effekter av bakljusanvändning i dagsljus undersöktes med ett fältexperiment, en enkätstudie, och en observationsstudie. Fältexperimentet mätte passerande bilars sidoavstånd till stillastående bil, som effekt av om den hade tända eller släckta bakljus. Enkäten mätte bilförares uppfattning om säkerhet och synlighet beroende på bakljusanvändning, samt deras erfarenheter, preferenser och egen användning av bakljus i dagsljus. Resultaten visade att tända bakljus ger större sidoavstånd vid passage. Stillastående bil med tända bakljus tolkas som mer sannolik att vara igång och därmed kunna börja köra. Tända bakljus föredras och skattas ge bättre synlighet och trafiksäkerhet, vilket står i kontrast till EU-lagstiftningen som tillåter släckta bakljus i dagsljus. Endast en liten andel av bilförarna vet om att de kör med släckta bakljus i dagsljus, medan majoriteten faktiskt kör med släckta bakljus. Slutsatsen är att tända bakljus i dagsljus ger bättre trafiksäkerhet (vilket motsäger skäl för rådande EU-lagstiftning); efterfrågas av bilförare; att majoriteten av förare inte vet om att de kör med släckta bakljus i dagsljus; och att det därför finns anledning att revidera lagstiftningen rörande bakljus inom EU och införa krav på tända bakljus i dagsljus.

Effects of rear-light usage were examined via a field experiment, a questionnaire study, and an observational study. The field experiment measured passing vehicles' lateral distance to a stationary car, as an effect of lit or unlit rear lights. The questionnaire measured car drivers' perceptions regarding safety and visibility depending on rear-light usage, and their experiences, preferences, and own usage of rear lights in daylight. The results showed that lit rear lights give greater lateral distance when being passed by. A stationary car with lit rear lights is interpreted as more likely to be running and therefore as more likely to start driving. Lit rear lights are preferred and are estimated to give better visibility and traffic safety. Only a small proportion of drivers know that they drive with unlit rear lights in daylight, whilst the majority actually do drive with unlit rear lights. The conclusion is that lit rear lights by daylight improve traffic safety (which contradicts claims behind the EU legislation); is preferred by drivers; that the majority of drivers do not know that they drive with unlit rear lights in daylight; and that there therefore is reason to revise the EU legislation concerning rear lights to make lit rear lights in daylight mandatory.

Many European train drivers face major changes in their work with the introduction of the new train-protection system, the European Rail Traffic Management System (ERTMS), as information retrieval shifts from outside to in-cab, and a new rulebook is introduced. Therefore, many train drivers have to be educated in a short time, to make the transition safe and efficient. The purpose was to find out how a successful ERTMS practice can be designed in a physically low-fidelity but highly functional train-driving simulator. An experimental design was used, with 16 drivers divided into two groups: one group practiced in a simulator, and the other in reality. Standard training methodology was used, and the learning outcome was assessed by both measuring driving errors and via instructor evaluation of a simulator test. The drivers also filled in a questionnaire to capture how different factors, such as repeated practice, experience, and self-estimated confidence, correlate with performance. Results show that the simulator group committed significantly fewer driving errors and received significantly higher scores from the instructor. In addition, the simulator group's better performance is mostly caused by the possibility of repeated training of different special cases. The findings also imply that several of the more common special cases on the ERTMS can hardly be provoked in real train driving. Furthermore, this work strengthens the theory that novices can hardly estimate their own ability. Therefore, we argue that this type of low-fidelity simulator is well suited for research purposes, for practicing special cases, and for train operation companies to assess drivers' skills.

Utöver en ökad kroppslig skörhet med stigande ålder, kan äldre förare ha en större risk för trafikolyckor på grund av medicinska tillstånd, läkemedel och funktionsnedsättningar. Specifika medicinska tillstånd och kognitiva nedsättningar kan påverka en säker bilkörning, som till exempel hjärtsjukdomar, demens och stroke. För körkortsinnehav finns vissa medicinska krav fastställda men när det gäller nedsättningar i kognitiva funktioner kan det vara svårt att bedöma huruvida dessa inverkar på körförmågan. Bakgrunden till projektet är att det finns få tillförlitliga tester som specifikt har tagits fram för bilkörning och lämplighet för körkortsinnehav. Syftet med studien var därför att utvärdera en ny testmetod, i form av ett simulatorprogram, för användning vid körkortsmedicinska utredningar inom hälso- och sjukvården för patienter med kognitiva nedsättningar, och att jämföra olika åldersgruppers prestationer. Studien undersökte även om prestationen och resultaten skiljde sig åt mellan olika åldrar och hur väl simulatortestet överensstämmer med andra välkända kognitiva tester.

I studien ingick 67 friska deltagare i åldrarna 19–87 år, vilka delades upp i två åldersgrupper. En korrelationsanalys mellan resultat på simulatortestet och två traditionella kognitiva test (TMT och UFOV) genomfördes. Vidare undersöktes även den interna konsistensen av simulatorns del tester samt genomfördes en multipel regressionsanalys. Resultaten påvisade god intern konsistens (α = .83). Det framkom signifikanta och måttliga korrelationer (p < .001, rs > .50) gällande reaktionstider för alla deltester och UFOV 3, och även i de flesta fall med TMT A. Analyserna på visade också signifikanta skillnader (p < .001) och stora effektstorlekar (r > .60) mellan åldersgrupperna på alla tester gällande reaktionstider och för position/placering. Med anledning av de positiva resultaten för kriterievaliditet, särskilt för TMT A och UFOV 3, framkommer en tydlig potential för simulatorn att användas som ett komplement i kognitiva bedömningar för körkortslämplighet. För framtida bruk behövs dock kliniska studier för att ytterligare undersöka dess användbarhet för patienter med kognitiva nedsättningar.

Emergency vehicles (EVs) are at high risk of accidents during emergency driving. To make use of countermeasures to mitigate these risks, it is important to understand under what circumstances EV-related accidents occur. The common risk factors for EV-related accidents were examined through a systematic literature review. A total of 22 articles were examined for risk factors associated with EV-related accidents. The most reported risk factors were, in order of frequency, intersections, daytime, dry roads, clear weather, urban roads, traffic signals, and angular collisions. The articles were also reviewed for suggested countermeasures to mitigate the risk factors. The most commonly suggested countermeasures were driver training for EV operators, educating the public, exercising caution at intersections, wearing a seatbelt, and intelligent vehicle technologies. Cooperative intelligent transport systems (C-ITSs) have the potential to mitigate the risks of EV-related accidents. Therefore, three C-ITS services were investigated: EV approaching, EV preemption, and geofencing. They could all be used to inform, warn, or control aspects of driving. Each suggested service has the potential to decrease risk factors for EV-related accidents. The current literature review provides guidance on under what circumstance and in what form C-ITSs could be beneficial to prevent EV-related accidents. Further research is needed to examine behavior when drivers are introduced to C-ITSs.

Objectives: This study investigated which work-related stressors are rated highest by train drivers and which are strongest correlated with consideration to change profession.

Methods: In a questionnaire, a total of 251 Swedish train drivers rated 17 work-related stressors, to which extent they had considered quitting their profession, and if they had experienced a PUT (person under train) accident.

Results: PUTs (when experienced) and irregular work hours are the main stressors, but the strongest predictors of consideration to change profession are those that are encountered often, and last over time (eg, irregular work hours, r = 0.61, and major organizational changes, r = 0.51).

Conclusions: For effective reduction of stress and improved job satisfaction, focus should be on aspects that affect everyday life for drivers, such as better working shifts, less delays, and improved social climate.

Det övergripande syftet var att undersöka identifieringsljusets synlighetsfrämjande och trygghetsskapande effekter. 

Ett fältexperiment med stationärt polisfordon med identifieringsljus genomfördes tre fredagskvällar utmed gångstråk vid ett torg, där många människor passerade och träffades. Totalt 2 883 passerande fotgängare registrerades med avseende på om de sett polisfordonet eller inte, beroende på om identifieringsljuset var påslaget eller inte. Dessutom jämfördes effekten av identifieringsljus i dagsljus och mörker, på kortare och längre siktavstånd, samt med högre och lägre polisfordon. 

Två enkätundersökningar genomfördes också, varav en riktad till allmänheten och en till poliser i ingripandeverksamhet samt trafikpoliser (12 723 respektive 1 132 fullständigt besvarade enkäter). I dem undersöktes hur stor synlighetsfrämjande effekt identifieringsljuset anses ha samt hur mycket tryggare allmänheten känner sig och hur mycket lugnare trafiken blir när polisen är synligt närvarande. I tillägg undersöktes omfattningen av identifieringsljusets användning och i vilken omfattning allmänheten lagt märke till denna användning. Allmänhetens skattningar jämfördes också med polisens skattningar, både vad gäller identifieringsljusets synlighetsfrämjande effekt och hur mycket tryggare allmänheten känner sig när polisen är synligt närvarande.

The general purpose was to examine the visibility-enhancing and security-enhancing effects of police cruise light. 

A field experiment with a stationary police vehicle with cruise light was conducted three Friday nights at pedestrian paths by a town square, with many people passing by and meeting each other. In total 2,883 passing pedestrians were registered with regard to if they had seen the police vehicle or not, depending on whether the cruise light was on or not. The effect of cruise light was also compared in daylight versus darkness, on shorter versus longer viewing distance, and on a higher versus a lower police vehicle. 

Two questionnaire studies were also conducted, whereof one for the general public and one for the police in intervention activities and traffic police (12,723 and 1,132 finished questionnaires, respectively). The questions concerned how visibility-enhancing the cruise light is rated to be and how much more secure the general public feels and how much calmer the traffic is when the police is visibly present. Additionally, the extent of cruise light usage was examined, as well as to what extent the general public has taken notice of this usage. The ratings of the general public were also compared to the ratings of the police, with regard to both the visibility-enhancing effect of cruise light and to how much more secure the general public feels when the police is visibly present.

A simulator driving test (SDT) and two neuropsychological tests, the Useful Field of View (UFOV) test and the Test of Variables of Attention (TOVA) were evaluated with regard to validity for fitness to drive on 51 young clients diagnosed with attention deficit hyperactivity disorder (ADHD), 33 of whom also had autism spectrum disorder (ASD), and 38 adolescents without a neurodevelopmental diagnosis. The results show generally much greater variability and significantly poorer performance in the SDT and the TOVA for clients with ADHD/ASD compared with the control group. The SDT results were strongly intratest correlated, but had no interest correlation with either the UFOV test or the TOVA. The greater variability among clients with ADHD/ASD suggests greater effort and susceptibility to motivational issues and decline in sustained attention over several tests. In conclusion, the SDT is sensitive and has good face validity, and the TOVA is sensitive to neuropsychological aspects of safe driving. The SDT and the TOVA thus complement each other, and discrepancy between test scores calls for special consideration. © 2021 The Author(s). Published with license by Taylor & Francis Group, LLC.

Objective To examine the effect of attention-deficit/hyperactivity disorder (ADHD) on differences in driving behavior and risk perception, in experienced drivers. Methods A total of 147 experienced drivers participated in the study. Drivers with ADHD (n = 91) were compared to an age-matched control group of drivers (n = 56) with no neuropsychiatric diagnoses. A simulator driving test (SDT) was used in the study and included a driving scenario with various traffic environments to examine any differences in number of collisions, number of speedings, risk index (based on 12 risky situations), speed adaptation (based on 19 road sections), mean speed, and preferred speed, between the two groups. The participants also completed a questionnaire about their driving behavior. Results No differences in the simulator driving test were found between the ADHD group and the control group. No adverse effects of ADHD were found for any of the measures, i.e., collisions, number of speeding, risk index, speed adaptation, mean speed and preferred speed. The only significant group difference was that drivers with ADHD rated themselves lower on concentration. Conclusions Participants with ADHD and the control group drove remarkably similarly in the simulator driving test and rated themselves similarly regarding how they drive. The results contribute to state that ADHD drivers are less deviant than asserted by previous research.

Objectives: The internship period of the Swedish train driver education was examined in terms of which types of situations can be sufficiently encountered in order to develop expertise to handle them safely and efficiently, and to quantify and specify the gap in expertise between expert and novice drivers in terms of risk of error and time efficiency. Focus was on special cases (i.e., situations that occur rarely but may cause severe accidents if not handled correctly and efficiently).

Methodology: Data on which situations and special cases a driver's student can be expected to experience during the internship period were collected via a web-based questionnaire. Also, ratings of expectations on novice and expert drivers were obtained from train driver educators, employers, and instructors with the purpose of comparing the expectations with the novices practical experience.

Results and conclusions: The main results suggest that many special cases are generally insufficiently practiced during the internship and therefore should be practiced in simulators; that both experienced and novice drivers prioritize safety over efficiency; and that expectations on novice drivers are realistic considering their limited professional expertise. © 2021, The Author(s).

Tekniska förutsättningar för att undersöka effekterna av insatser för att minska trängsel i kollektivtrafiken med objektiva mått undersöktes, i syfte att förbereda för framtida studier. Insatserna kan handla dels om samhällsinsatser där grupper av kollektivtrafikresenärer får sina restider mer utspridda över dygnet, dels om insatser där resenärerna uppmuntras att resa med avgångar utan trängsel. Fem enkätundersökningar med totalt 7605 respondenter genomfördes också, i syfte att undersöka (1) om utspridda skolstartstider i Göteborg och Linköping haft mätbar effekt på upplevd trängsel under hösten 2020; (2) resenärernas upplevelser av trängsel, oro för att bli smittade, och trängseltolerans; och (3) hur information om fyllnadsgrad påverkar resval både generellt och för olika resenärskategorier.