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The purpose was to investigate which detailed characteristics of shift schedules that are seen as problems to those exposed. A representative national sample of non-day workers (N = 2031) in Sweden was asked whether they had each of a number of particular work schedule characteristics and, if yes, to what extent this constituted a "big problem in life". It was also inquired whether the individual's work schedules had negative consequences for fatigue, sleep and social life. The characteristic with the highest percentage reporting a big problem was "short notice (<1 month) of a new work schedule" (30.5%), <11 h off between shifts (27.8%), and split duty (>1.5 h break at mid-shift, 27.2%). Overtime (>10 h/week), night work, morning work, day/night shifts showed lower prevalences of being a "big problem". Women indicated more problems in general. Short notice was mainly related to negative social effects, while <11 h off between shifts was related to disturbed sleep, fatigue and social difficulties. It was concluded that schedules involving unpredictable working hours (short notice), short daily rest between shifts, and split duty shifts constitute big problems. The results challenge current views of what aspects of shift work need improvement, and negative social consequences seem more important than those related to health. [ABSTRACT FROM AUTHOR]

Objective: We investigated the prognostic impact of sleep complaints in women with CHD and also examined whether the association between sleep problems and cardiac events could be explained by depression.Methods: All women patients, aged 65 or under who were admitted with an acute coronary syndrome between 1991 and 1994 in Stockholm, were followed for 5 years for recurrent coronary events. Sleep complaints and depression were measured at baseline using standardized questionnaires. Quality of sleep, restorative function of sleep, and snoring were assessed by the Karolinska Sleep Questionnaire (KSQ), and depressive symptoms by a questionnaire developed by Pearlin.Results: Poor sleep quality was associated with recurrent cardiac events. After multivariate adjustment for age, and standard risk factors, the hazard ratio (HR) for women with poor as compared with good sleep quality was 2.5 (95% CI: 1.2-5.2). Controlling for depression did not change this result substantial. Not waking up well-rested yielded a similarly increased risk (HR = 2.4; 95% CI: 1.2-4.6). Women with both poor sleep quality and depression had a worse prognosis than women free from these complaints (HR = 2.6; 95% CI: 1.0-6.4). Heavy snoring was not related to prognosis.Conclusions: Our results indicate that poor sleep and sleep without a restorative function are associated with poor prognosis in female coronary patients. This association is not explained by depressive symptoms or by standard coronary risk factors. [ABSTRACT FROM AUTHOR]

Summary Workers often attribute poor sleep to factors at work. Despite the large number of workers with sleep disturbances, there is a lack of consensus on the relationship between the work environment and sleep. The purpose of this systematic review therefore was to conduct a comprehensive evaluation. To this end, we employed standardized methods to systematically locate, review, and tabulate the results of prospective or randomized studies of the impact of work factors on sleep disturbances. From the 7981 articles located in five databases, 24 fulfilled our inclusion criteria and formed the base of the review including meta-analyses of the effect sizes. Results showed that the psychosocial work variables of social support at work, control, and organizational justice were related to fewer sleep disturbances, while high work demands, job strain, bullying, and effort-reward imbalance were related to more future sleep disturbances. Moreover, working a steady shift was associated with disturbances while exiting shift work was associated with less disturbed sleep. We conclude that psychosocial work factors and the scheduling of work have an impact on sleep disturbances and this might be utilized in the clinic as well as for planning work environments. Future research needs to employ better methodology and focus on underlying mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Few studies have examined the extent of driver sleepiness during a long distance morning trip. Sleepiness at this time may be high because of night work, waking early to commence work or travel, sleep disorders and the monotony of driving long distances. The objective of this study was to estimate the prevalence of chronic sleepiness (Epworth sleepiness score ≥10) and sleep restriction (≤5h) in a sample of 649 drivers. Participants driving between 08:00 and 10:00 on three highways in regional Australia participated in a telephone interview. Approximately 18% of drivers reported chronic sleepiness. The proportions of night workers (NW) and non-night workers (NNW) with chronic sleepiness were not significantly different but males reported a significantly greater proportion of chronic sleepiness than females. The NW group had a significantly greater proportion of drivers with ≤5h of sleep in the previous 24 and 48h, fewer nights of full sleep (≤4), acute sleepiness and longer weekly work hours. The NW group reported driving a significantly longer distance at Time 1 (Mean=140.29±72.17km, versus 117.55±89.74km) and an additional longer distance to complete the journey (Mean=89.33±95.23km, versus 64.77±94.07km). The high proportions of sleep restriction and acute sleepiness among the NW group, and the amount of chronic sleepiness in the NW and NNW groups reported during a long distance morning trip may be of concern for driver safety. [Copyright &y& Elsevier]

Abstract: Previous studies indicate that the effect of a given shift schedule may depend on individual factors. The aim of the present study was to investigate whether a misfit between individual preferences and actual working hours affected the association between working hours and self-reported indicators of health and well-being. The study population consisted of 173 female eldercare workers who mainly worked day or evening shifts. We combined self-reported questionnaire data on preferences with actual work schedules during a four-week period. The study showed that a misfit between preferences on one hand and “non-day work”, “weekend work” or “only a few consecutive days off” on the other hand was associated with an increased dissatisfaction with working hours and/or an increase in the intention to leave the workplace due to one''s working hours. [Copyright &y& Elsevier]

Abstract: A moving base driving simulator experiment was carried out in order to investigate the effects of milled rumble strips on driver fatigue. There were rumble strips both at the edge line and centre line. Four different physical designs of milled rumble strips (yielding noise values from 1.5 to 16dBA) and two placements on shoulder were used in the experiment. Sound and vibrations from real milled rumble strips were reproduced in the simulator. In total 35 regular shift workers drove during the morning hours after a full night shift. The main results showed an increase in sleepiness indicators (EEG alpha/theta activity, eye closure duration, standard deviation of lateral position, subjective sleepiness) from start to before hitting the rumble strip, an alerting effect in most parameters (not subjective sleepiness) after hitting the strip. The alertness enhancing effect was, however, short and the sleepiness signs returned 5min after the rumble strip hit. Essentially no effects were seen due to type of strip. It was concluded that various aspects of sleepiness are increased before hitting a rumble strip and that the effect is very short-lived. Type of strip, as used in the present study did not have any effect. [Copyright &y& Elsevier]

Abstract: It is often claimed that shift workers give priority to long series of days off and therefore prefer compressed work schedules at the expense of what is optimal for long-term health. The aim of the present study was to evaluate the attitude to six new shift systems among a randomly selected sample of police officers. The results showed that the most popular shift system was a rapidly, forward, rotating schedule with at least 16h of rest between shifts, despite that it had fewer days off compared with some of the compressed shift systems. However, the individual differences were large and many individuals (32%) disliked the rapidly rotating shift system. Young age was associated with a positive attitude to the rapidly rotating shift system. The attitude to the shift system was also influenced by the present schedule, and shift systems that were similar to the present work hours received more positive evaluation. Sleep and health complaints showed no association with the attitude to the shift systems. In conclusion, the shift workers attitude to the new schedules was partly in agreement with the ergonomic recommendations of the design of three-shift systems that will facilitate sufficient sleep and minimize negative health consequences. [Copyright &y& Elsevier]

Abstract: Sleep is an important factor in relation to accidents, long-term health and mortality. Our group has had a long-term commitment to research on sleep regulation and its consequences. Over the years we have demonstrated pronounced effects of night work on sleep and alertness, including electroencephalographically determined sleep during work. We have also demonstrated that experimental displacement of sleep will result in short sleep at daytime and increased physiological sleepiness at night and developed mathematical models for prediction of sleep duration, as well as of sleepiness and risk of sleep-related accidents. We have also looked at the concept of sleep quality and found it dependent on sleep duration, sleep continuity and content of sleep stages 3 and 4. Sleep is also clearly disturbed in patients on long-term sick leave for burnout or in non-patients with high burnout scores, in particular sleep fragmentation is increased and sleep efficiency and sleep stages 3 and 4 (SWS — deep sleep) decreased. The fragmentation in turn seems related to endocrine changes. Present work is focused on bringing this work together, connecting the links from stress to sleep to metabolic changes to disease and long-term sickness absence. [Copyright &y& Elsevier]

Ships typically operate on a 24/7 basis giving rise to a wide variety of working time arrangements and watch keeping schedules. Typically, these can be divided into 2-watch systems (where two watch keepers/teams share the 24-h period) and 3-watch systems (where three watch keepers/teams share the 24-h period). The current study uses the three-process model of alertness regulation to compare these systems in terms of the amount of severe sleepiness that is predicted to take place on watch and the amount of sleep that is predicted to occur while off watch. Separate predictions are calculated for individuals characterised as morning and evening chronotypes. Comparing 2-watch systems, highest levels of severe sleepiness were seen for evening types working 0000–1200 within the 12on12off system. The longest sleep per 24 h day was also found for evening types, but for those working the 1200–0000 watch within the 12on12off system. Total daily sleep duration ranged between 268 and 445 min. However, the picture is complex and the lowest risk of severe sleepiness while on watch is not necessarily correlated with the maximal time available for rest and recuperation when off watch. For 3-watch systems, the "five-and-dime" system (changeover times: 02-07-12-17-22) stands out having the lowest prevalence of severe sleepiness on watch and the longest amount of predicted daily sleep off watch. Considerable differences exist between morning and evening types offering the opportunity for considerable improvement in sleep amount for fixed (but not rotating) systems when individual chronotype is considered in watch scheduling. It is concluded that 3-watch systems, although economically costlier, have clear advantages over 2-watch systems, but that a perfect system that fits all does not exist due to the considerable impact of individual differences related to sleep/wake regulation. • Two-watch systems are worse in terms of sleep of fatigue than three-watch systems. • Diurnal preference considerably affects fatigue levels and the possibilities for sleep. • Rotating schedules are not necessarily worse than fixed schedules. [ABSTRACT FROM AUTHOR]

Abstract: Cox proportional hazard models were used to study relationships between the event that a driver is leaving the lane caused by sleepiness and different indicators of sleepiness. In order to elucidate different indicators’ performance, five different models developed by Cox proportional hazard on a data set from a simulator study were used. The models consisted of physiological indicators and indicators from driving data both as stand alone and in combination. The different models were compared on two different data sets by means of sensitivity and specificity and the models’ ability to predict lane departure was studied. In conclusion, a combination of blink indicators based on the ratio between blink amplitude and peak closing velocity of eyelid (A/PCV) (or blink amplitude and peak opening velocity of eyelid (A/POV)), standard deviation of lateral position and standard deviation of lateral acceleration relative road (ddy) was the most sensitive approach with sensitivity 0.80. This is also supported by the fact that driving data only shows the impairment of driving performance while blink data have a closer relation to sleepiness. Thus, an effective sleepiness warning system may be based on a combination of lane variability measures and variables related to eye movements (particularly slow eye closure) in order to have both high sensitivity (many correct warnings) and acceptable specificity (few false alarms). [Copyright &y& Elsevier]

Abstract: Young drivers are over-represented in nighttime traffic accidents and several studies have suggested that many accidents are associated with elevated sleepiness levels. It has been suggested that there may be a connection between lowered wake capacity and functional sensory motor skills on the one hand and sleep deprivation at the circadian low in young drivers on the other. Performance during a 45/min evening and night drive among young (n =10, age range 18–24 years) and elderly (n =10, age range 55–64 years) subjects was studied using a moving base driving simulator. EEG was measured continuously. Every 5min, subjects were rated on the Karolinska Sleepiness Scale (KSS). Saliva cortisol was assessed before and after each drive. The results showed that sleepiness increased across each drive and was higher among young drivers at night. Relative EEG power increased among older drivers for frequencies of 10–16Hz. The sigma 1 frequency band (12–14Hz) proved particularly sensitive to sustained driving, and was elevated among subjects in the elderly group. Cortisol levels before and after the evening and night drive showed higher mean levels for elderly subjects. The present study has demonstrated that young drivers were more sleepy while driving at night. The effects could represent a mobilization of effort and a reorganization of brain firing pattern among older subjects, possibly reflecting better ability and effort to resist sleepiness. [Copyright &y& Elsevier]

Abstract: Objective: This study investigated whether verbal rating sleepiness will itself affect sleepiness and performance. Methods: Thirteen healthy male volunteers (mean age, 26.9 years) performed two 40-min vigilance tests, one of which involved verbal ratings every 4min using the Karolinska sleepiness scale and another of which did not involve any ratings during the test. Results: Repeated rating of sleepiness significantly reduced post-test sleepiness and improved the subjective perception of performance, and also reduced alpha power density (i.e., a physiological indicator of sleepiness). However, performance was not improved by the ratings. Conclusions: The act of rating affects subjective and EEG measures of sleepiness. Presumably this occurs through the modest stimulation involved in this act. Significance: Methodologically one should be aware of subtle effects of the rating situation on sleepiness. From a practical point of view, it would be important for safety management since subjective sleepiness and performance are easily dissociated, which might interfere with risk perception. [Copyright &y& Elsevier]

• Some suicides are attempted by crashing into a heavy vehicle. • Studies on heavy vehicle drivers involved in these types of crashes are lacking. • We present a one-year follow-up study of heavy vehicle drivers involved in a suicide crash. • Two thirds reported some kind of negative consequences on their well-being. • A routine post-crash evaluation of the need for psychological treatment is advisable. Train and heavy vehicle drivers can experience a traumatic event caused by people attempting suicide by crashing into their vehicles or jumping in front of them. While there are a number of studies on train drivers showing the negative consequences these events can have on their well-being, there are no studies on heavy vehicle drivers involved in these types of crashes. In the current study, we surveyed Finnish heavy vehicle drivers (N = 15) involved in a suicide crash in the year 2017 regarding their experiences and coping approximately one month (T1) and one year (T2) after the crash. Ten of these drivers reported one or various combinations of measurable consequences such as minor physical injuries, shorter or longer sickness absences, significant posttraumatic stress symptoms (measured using the Impact of Events Scale-Revised) and requiring psychological help. Posttraumatic stress symptoms decreased over time; however, three out of the four drivers who had a high IES-R score at T1 were still around the IES-R cut-off score at T2. This research raises questions whether and what kind of support heavy vehicle drivers who have been involved in a suicide crash should be given. [ABSTRACT FROM AUTHOR]

Evidence supporting the effectiveness of cognitive behavior therapy (CBT) for stress-related illness is growing, but little is known about its mechanisms of change. The aim of this study was to investigate potential mediators of CBT for severe stress in form of clinical burnout, using an active psychological treatment as comparator. We used linear mixed models to analyze data from patients (N = 82) with clinical burnout who received either CBT or another psychological treatment in a randomized controlled trial. Potential mediators (i.e., sleep quality, behavioral activation, perceived competence, and therapeutic alliance) and outcome (i.e., symptoms of burnout) were assessed weekly during treatment. The results showed that the positive treatment effects on symptoms of burnout favoring CBT (estimated between-group d = 0.93) were mediated by improvements in sleep quality, ab = -0.017, 95% CIasymmetric [-0.037, -0.002], and increase in perceived competence, ab = -0.037, 95% CIasymmetric [-0.070, -0.010]. Behavioral activation, ab = -0.004 [-0.016, 0.007], and therapeutic alliance, ab = 0.002 [-0.006, 0.011], did not significantly mediate the difference in effects between the treatments. Improving sleep quality and increasing perceived competence may thus constitute important process goals in order to attain symptom reduction in CBT for clinical burnout. [ABSTRACT FROM AUTHOR]

Highlights • Company employees are sometimes used as research participants in traffic safety research. • There are several important ethical and methodological implications. • Three types of data were collected. • We offer an extensive discussion. Abstract The use of company employees as experimental participants when testing products, technology or paradigms developed by the same company raises questions about bias in results and research ethics. We aimed to investigate the prevalence of studies authored by car company researchers with car company employees as participants, to assess the risk of bias in such studies, to investigate journal editors' opinions in the field of traffic safety regarding these procedures, and to offer a general discussion about ethical and methodological implications. Three types of data were collected. We (i) examined guidelines and recommendations for authors in eleven selected peer-reviewed journals in the area of traffic safety; (ii) surveyed editors of these journals; and (iii) reviewed articles authored by researchers from a selected group of car manufacturers and published in these journals during 2011–2015. Guidelines and recommendations for authors in the included journals did not mention whether and under what circumstances company employees can be research participants, nor did publishers' general guidelines. However, three out of the four editors who responded to our survey believed that this issue of private company researchers using participants from the same company deserves to be explicitly addressed in their journal's guide for authors. The total number of regular articles and conference papers during 2011–2015 in the eleven journals reviewed was 6763; 95 (1.4%) listed at least one car manufacturer in the authors' affiliations; and out of these, nine included company employees as participants. In summary, company employees are seldom (0.13%) used as research participants in traffic safety research. Nevertheless, the use of company employees as research participants raises questions about bias in results as well as about incursions into the participants' autonomy. [ABSTRACT FROM AUTHOR]

Highlights • This experimental study addressed the effect of sleep deprivation on the response to the Trier Social Stress Test (TSST) in young and older adults. • At baseline, cortisol levels and stress ratings were higher in sleep-deprived participants. • Older adults had higher autonomic activation and felt more stressed at baseline than young adults. • The response to and recovery from the TSST were not significantly different after one night of sleep deprivation than after normal sleep. Abstract Sleep loss and psychosocial stress often co-occur in today’s society, but there is limited knowledge on the combined effects. Therefore, this experimental study investigated whether one night of sleep deprivation affects the response to a psychosocial challenge. A second aim was to examine if older adults, who may be less affected by both sleep deprivation and stress, react differently than young adults. 124 young (18–30 years) and 94 older (60–72 years) healthy adults participated in one of four conditions: i. normal night sleep & Placebo-Trier Social Stress Test (TSST), ii. normal night sleep & Trier Social Stress Test, iii. sleep deprivation & Placebo-TSST, iv. sleep deprivation & TSST. Subjective stress ratings, heart rate variability (HRV), salivary alpha amylase (sAA) and cortisol were measured throughout the protocol. At the baseline pre-stress measurement, salivary cortisol and subjective stress values were higher in sleep deprived than in rested participants. However, the reactivity to and recovery from the TSST was not significantly different after sleep deprivation for any of the outcome measures. Older adults showed higher subjective stress, higher sAA and lower HRV at baseline, indicating increased basal autonomic activity. Cortisol trajectories and HRV slightly differed in older adults compared with younger adults (regardless of the TSST). Moreover, age did not moderate the effect of sleep deprivation. Taken together, the results show increased stress levels after sleep deprivation, but do not confirm the assumption that one night of sleep deprivation increases the responsivity to an acute psychosocial challenge. [ABSTRACT FROM AUTHOR]

Airline pilots’ sleep and on-duty alertness are important focus areas in commercial aviation. Until now, studies pertaining to this topic have mainly focused on specific characteristics of flights and thus a comprehensive picture of the matter is not well established. In addition, research knowledge of what airline pilots actually do to maintain their alertness while being on duty is scarce. To address these gaps in research knowledge, we conducted a field study on a representative sample of the airline pilots of a medium-sized airline. The sample consisted of 90 pilots, of whom 30 flew long-haul (LH) routes, 30 short-haul (SH) routes, and 30 flew both. A total of 86 pilots completed the measurements that lasted for almost two months per pilot. The measurements resulted in a total of 965 flight duty periods (FDPs) including SH flights and 627 FDPs including LH flights. During the measurement periods, sleep was measured by a diary and actigraphs, on-duty alertness by the Karolinska Sleepiness Scale (KSS) in all flight phases, and on-duty alertness management strategies by the diary. Results showed that SH and LH FDPs covering the whole domicile night (00:00–06:00 at home base) were most consistently associated with reduced sleep-wake ratio and subjective alertness. Approximately every 3rd FDP falling into this category involved a reduced sleep-wake ratio (1:3 or lower) and every 2nd a reduced level of subjective alertness (KSS rating 8–9 in at least one flight phase). The corresponding frequencies for the SH and LH FDPs that partly covered the domicile night were every 10th and every 5th FDP and for the pure non-night FDPs every 30th and every 36th FDP, respectively. The results also showed that the pilots tended to increase the use of effective on-duty alertness management strategies (consuming alertness-promoting products and taking strategic naps) in connection with the FDPs that overlapped the domicile night. Finally, the results showed that the frequency of flights involving reduced subjective alertness depended on how alertness was assessed. If it was assessed solely in the flight phase just before starting the landing procedures (top of descent) the phenomenon was less frequent than if the preceding cruise phase was also taken into account. Our results suggest that FDPs covering the whole domicile night should be prioritised over the other FDPs in fatigue management, regardless of whether an FDP is a short-haul or a long-haul. In addition, the identification of fatigue in flight operations requires one to assess pilots’ alertness across all flight phases, not only at ToD. Due to limitations in our data, these conclusions can, however, be generalise to only LH FDPs during which pilots can be expected to be well acclimatised to the local time at their home base and SH night FDPs that include at least 3 h of flying in the cruise phase. [ABSTRACT FROM AUTHOR]

In this cross-sectional study associations were examined between eight shift schedule characteristics with shift-specific sleep complaints and need for recovery and generic health and performance measures. It was hypothesized that shift schedule characteristics meeting ergonomic recommendations are associated with better sleep, need for recovery, health and performance. Questionnaire data were collected from 491 shift workers of 18 companies with 9 regular (semi)-continuous shift schedules. The shift schedule characteristics were analyzed separately and combined using multilevel linear regression models. The hypothesis was largely not confirmed. Relatively few associations were found, of which the majority was in the direction as expected. In particular early starts of morning shifts and many consecutive shifts seem to be avoided. The healthy worker effect, limited variation between included schedules and the cross-sectional design might explain the paucity of significant results. [ABSTRACT FROM AUTHOR]

Objective: In this longitudinal two-wave study, bidirectional relations between work-related stress and sleep quality were examined. Moreover, it was investigated whether perseverative cognition is a potential underlying mechanism in this association, related to both work-related stress and sleep quality.Methods: A randomly selected sample of Dutch employees received an online survey in 2012 and 2013. Of all invited employees, 877 participated in both waves. Structural equation modeling was performed to analyze the data.Results: We found evidence for reversed relations between work-related stress and sleep quality. Specifically, when controlling for perseverative cognition, work-related stress was not directly related to subsequent sleep quality, but low sleep quality was associated with an increase in work-related stress over time. Moreover, negative bidirectional associations over time were found between perseverative cognition and sleep quality, and positive bidirectional associations were found between work-related stress and perseverative cognition. Lastly, a mediation analysis showed that perseverative cognition fully mediated the relationship between work-related stress and sleep quality.Conclusion: The study findings suggest that perseverative cognition could be an important underlying mechanism in the association between work-related stress and sleep quality. The bidirectionality of the studied relationships could be an indication of a vicious cycle, in which work-related stress, perseverative cognition, and sleep quality mutually influence each other over time. [ABSTRACT FROM AUTHOR]

Driver surveys are indispensable sources of information when estimating the role of sleepiness in crash causation. The purpose of the study was to (1) identify the prevalence of driving while sleepy among Finnish drivers, (2) determine the circumstances of such instances, and (3) identify risk factors and risk groups. Survey data were collected from a representative sample of active Finnish drivers ( N = 1121). One-fifth of the drivers (19.5%) reported having fallen asleep at the wheel during their driving career, with 15.9% reporting having been close to falling asleep or having difficulty staying awake when driving during the previous twelve months. Epworth Sleepiness Scale scores were found to be associated with both types of sleepiness-related driving instances, while sleep quality was associated only with the latter. Compared to women, men more often reported falling asleep at the wheel; the differences were somewhat smaller with respect to fighting sleep while driving during the previous twelve months. The reported discrepancy in sleepiness-related instances (high prevalence of fighting sleep while driving during the previous twelve months and lower proportion of actually falling asleep) identifies young men (⩽25 years) as one of the main target groups for safety campaigns. Approximately three-quarters of drivers who had fallen asleep while driving reported taking action against falling asleep before it actually happened. Furthermore, almost all drivers who had fallen asleep while driving offered at least one logical reason that could have contributed to their falling asleep. These data indicate some degree of awareness about driving while sleepy and of the potential pre-trip factors that could lead to sleepiness while driving, and supports the notion that falling asleep at the wheel does not come as a (complete) surprise to the driver. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Fatigue is related to a number of serious diseases, as well as to general well-being. It is also a major cause of sickness absence and use of health facilities. Still, the determinants of variations in fatigue are little investigated. The purpose of present study was to investigate the relationships between the daily variations of fatigue with sleep during the previous night, stress or disease symptoms during the same day — across 42 consecutive days of normal life. Methods: 50 individuals participated and gave diary reports and used an actigraph across the 42days. The data was analyzed using a multilevel approach with mixed model regression. Results: The analyses showed that the day-to-day variation in fatigue was related to (poor) sleep quality (p<.001) and (reduced) sleep duration (p<.01) the previous night, as well as to higher stress (p<.05), and to the occurrence of a cold or fever (p<.001) during the same day as the fatigue rating. Fatigue was also strongly related to poorer subjective health (p<.001) and sleepiness (p<.001) during the same day. Conclusion: The results indicate that prior sleep (and sleepiness) as well as stress and illness are consistently connected to how fatigue is experienced during normal living conditions. [Copyright &y& Elsevier]

Abstract: Even though police officers and prosecutors play a key role in traffic law application, little is known about their experiences, attitudes, and opinions regarding the complex issue of driver fatigue and the law. This paper is based on an extensive online survey collected from traffic (N =129) and local (N =100) police officers and prosecutors (N =96) in the context of Finnish traffic law, which forbids driving while fatigued in an article relating to a driver’s fitness to drive. While encountering fatigued drivers is very common for police officers, only a small proportion has received training about how to recognize and deal with fatigued drivers. Driving while extremely fatigued is considered rather or extremely negligent behavior by almost all respondents. Although agreement between these three groups exists regarding several issues, they disagree about whether the current law is specific enough, and whether experts might be valuable in court when discussing the possible contribution of fatigue to the cause of a crash. We discuss the application of the law and opinions about the current law formulation, experience and education, as well as general awareness and attitudes, taking into consideration the different nature of police and prosecutor work. [Copyright &y& Elsevier]

Abstract: Sleepiness has been identified as one of the most important factors contributing to road crashes. However, almost all work on the detailed changes in behavior and physiology leading up to sleep related crashes has been carried out in driving simulators. It is not clear, however, to what extent simulator results can be generalized to real driving. This study compared real driving with driving in a high fidelity, moving base, driving simulator with respect to driving performance, sleep related physiology (using electroencephalography and electrooculography) and subjective sleepiness during night and day driving for 10 participants. The real road was emulated in the simulator. The results show that the simulator was associated with higher levels of subjective and physiological sleepiness than real driving. However, both for real and simulated driving, the response to night driving appears to be rather similar for subjective sleepiness and sleep physiology. Lateral variability was more responsive to night driving in the simulator, while real driving at night involved a movement to the left in the lane and a reduction of speed, both of which effects were absent in the simulator. It was concluded that the relative validity of simulators is acceptable for many variables, but that in absolute terms simulators cause higher sleepiness levels than real driving. Thus, generalizations from simulators to real driving must be made with great caution. [Copyright &y& Elsevier]

Abstract: Driver sleepiness contributes to a considerable proportion of road accidents, and a fit-for-duty test able to measure a driver’s sleepiness level might improve traffic safety. The aim of this study was to develop a fit-for-duty test based on eye movement measurements and on the sleep/wake predictor model (SWP, which predicts the sleepiness level) and evaluate the ability to predict severe sleepiness during real road driving. Twenty-four drivers participated in an experimental study which took place partly in the laboratory, where the fit-for-duty data were acquired, and partly on the road, where the drivers sleepiness was assessed. A series of four measurements were conducted over a 24-h period during different stages of sleepiness. Two separate analyses were performed; a variance analysis and a feature selection followed by classification analysis. In the first analysis it was found that the SWP and several eye movement features involving anti-saccades, pro-saccades, smooth pursuit, pupillometry and fixation stability varied significantly with different stages of sleep deprivation. In the second analysis, a feature set was determined based on floating forward selection. The correlation coefficient between a linear combination of the acquired features and subjective sleepiness (Karolinska sleepiness scale, KSS) was found to be R =0.73 and the correct classification rate of drivers who reached high levels of sleepiness (KSS⩾8) in the subsequent driving session was 82.4% (sensitivity=80.0%, specificity=84.2% and AUC=0.86). Future improvements of a fit-for-duty test should focus on how to account for individual differences and situational/contextual factors in the test, and whether it is possible to maintain high sensitive/specificity with a shorter test that can be used in a real-life environment, e.g. on professional drivers. [Copyright &y& Elsevier]

Abstract: Sleepiness is related to factors such as the time of day, the time since awakening and the duration of prior sleep. The present study investigated whether actual road crashes could be predicted from a mathematical model based on these three factors (the Sleep/Wake Predictor—SWP). Data were derived from a population-based case-control study of serious injury crashes. Data on accident time (or control sampling time) and start and end of prior sleep were entered into the model (blind). The predicted sleepiness values were used in logistic regressions. The results showed a highly significant odds ratio (OR)=1.72 (confidence interval=1.41–2.09) for each incremental step of sleepiness on the output sleepiness scale (nine steps). There was also a significant interaction with blood alcohol level, showing high OR values for high sleepiness levels and alcohol levels above 50mg% (0.05g/dl). It was concluded that the model is a good predictor of road crashes beyond that of alcohol level, and that interaction between the two carries a very high risk. [Copyright &y& Elsevier]

Objective: The study examined the multivariate relationship between mental fatigue and different work-related (work load, work hours) and background/life style factors, as well as disturbed sleep.sec id="sec1">Methods: A total of 5720 healthy employed men and women living in the greater Stockholm area participated in a questionnaire study on cardiovascular risk factors. The data were analysed using a multiple logistic regression analysis with self-rated fatigue as the dependent variable.sec id="sec2">Results: Fatigue was predicted by disturbed sleep (4.31; 3.50–5.45, high immersion in work (4.17; 2.93–5.94), high work demands (2.39; 1.54–3.69), social support, being a female, being a supervisor and high age. Shift work, work hours (including overtime) and influence at work did not become significant predictors. With control for work demands a high number of work hours was associated with lower fatigue.Conclusion: Disturbed sleep is an important predictor of fatigue, apparently stronger than previously well-established predictors such as work load, female gender, lack of exercise, etc. [Copyright &y& Elsevier]

• We investigated change processes in guided self-help CBT for social anxiety disorder. • Intraindividual change in processes and outcome were analyzed from weekly assessments. • Avoidance unidirectionally predicted subsequent symptom reduction. • Several of the presumed processes were bidirectionally related to symptom change. • The study sheds light on process-outcome relations in treatment of social anxiety. Although cognitive behavior therapy (CBT) is an effective treatment for social anxiety disorder, little is known about the processes during treatment that bring about change. The aim of this study was to investigate whether the proposed processes of change according to the cognitive model of social anxiety disorder predicted subsequent symptom reduction in CBT delivered as therapist-guided bibliotherapy. We analyzed data from patients with social anxiety disorder (N = 61) who participated in an effectiveness trial of CBT in primary care. Seven putative processes and outcome (i.e., social anxiety) were assessed on a weekly basis throughout treatment. We used linear mixed models to analyze within-person relations between processes and outcome. The results showed a unidirectional effect of reduced avoidance on subsequent decrease in social anxiety. Further, we found support for reciprocal influences between four of the proposed processes (i.e., estimated probability and cost of adverse outcome, self-focused attention, and safety behaviors) and social anxiety. The remaining two processes, (i.e., anticipatory and post-event processing) did not predict subsequent social anxiety, but were predicted by prior symptom reduction. The findings support that several of the change processes according to the cognitive model of social anxiety disorder are involved in symptom improvement. [ABSTRACT FROM AUTHOR]