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Abstract Background In the UK, audiology services deliver the majority of tinnitus patient care, but not all patients experience the same level of service. In 2009, the Department of Health released a Good Practice Guide to inform commissioners about key aspects of a quality tinnitus service in order to promote equity of tinnitus patient care in UK primary care, audiology, and in specialist multi-disciplinary centres. The purpose of the present research was to evaluate utilisation and opinions on pathways for the referral of tinnitus patients to and from English Audiology Departments. Methods We surveyed all audiology staff engaged in providing tinnitus services across England. A 36-item questionnaire was mailed to 351 clinicians in all 163 National Health Service (NHS) Trusts identified as having a tinnitus service. 138 clinicians responded. The results presented here describe experiences and opinions of the current patient pathways to and from the audiology tinnitus service. Results The most common referral pathway was from general practice to a hospital-based Ear, Nose & Throat department and from there to a hospital-based audiology department (64%). Respondents considered the NHS tinnitus referral process to be generally effective (67%), but expressed needs for improving GP referral and patients' access to services. 'Open access' to the audiology clinic was rarely an option for patients (9%), nor was the opportunity to access specialist counselling provided by clinical psychology (35%). To decrease the number of inappropriate referrals, 40% of respondents called for greater awareness by referrers about the audiology tinnitus service. Conclusions Respondents in the present survey were generally satisfied with the tinnitus referral system. However, they highlighted some potential targets for service improvement including 1] faster and more appropriate referral from GPs, to be achieved through education on tinnitus referral criteria, 2] improved access to psychological services through audiologist training, and 3] ongoing support from tinnitus support groups, national charities, or open access to the tinnitus clinic for existing patients.

Abstract Background Insomnia is perhaps the most common sleep disorder in the general population, and is characterised by a range of complaints around difficulties in initiating and maintaining sleep, together with impaired waking function. There is little quantitative information on treatment pathways, costs and outcomes. The aims of this New Zealand study were to determine from which healthcare practitioners patients with insomnia sought treatment, treatment pathways followed, the net costs of treatment and the quality of life improvements obtained. Methods The study was retrospective and prevalence based, and was both cost effectiveness (CEA) and a cost utility (CUA) analysis. Micro costing techniques were used and a societal analytic perspective was adopted. A deterministic decision tree model was used to estimate base case values, and a stochastic version, with Monte Carlo simulation, was used to perform sensitivity analysis. A probability and cost were attached to each event which enabled the costs for the treatment pathways and average treatment cost to be calculated. The inputs to the model were prevalence, event probabilities, resource utilisations, and unit costs. Direct costs and QALYs gained were evaluated. Results The total net benefit of treating a person with insomnia was $482 (the total base case cost of $145 less health costs avoided of $628). When these results were applied to the total at-risk population in New Zealand additional treatment costs incurred were $6.6 million, costs avoided $28.4 million and net benefits were $21.8 million. The incremental net benefit when insomnia was "successfully" treated was $3,072 per QALY gained. Conclusions The study has brought to light a number of problems relating to the treatment of insomnia in New Zealand. There is both inadequate access to publicly funded treatment and insufficient publicly available information from which a consumer is able to make an informed decision on the treatment and provider options. This study suggests that successful treatment of insomnia leads to direct cost savings and improved quality of life.

Knowledge about cabin crew fatigue associated with ultra-long range (ULR) flights is still limited. Current ULR scheduling for cabin crew is therefore predominantly based on flight crew data. Cabin crews' views on fatigue, and their strategies for mitigating it, have seldom been sought. To better understand the causes and consequences of cabin crew fatigue, semi-structured focus group discussions were held. Thematic analysis was undertaken with data from 25 cabin crew. Participants indicated that the consequences of fatigue are twofold, affecting 1) cabin crew health and wellbeing and 2) safety (cabin, passenger and personal) and cabin service. While the primary causes of fatigue were sleep loss and circadian disruption, participants also identified other key factors including: insufficient rest, high workload, the work environment, a lack of company support, and insufficient fatigue management training. They highlighted the importance of sufficient rest, not only for obtaining adequate recovery sleep but also for achieving a work-life balance. They also highlighted the need for company support, effective communication, and management's engagement with cabin crew in general. We recommend that priority is given to fatigue management training for cabin crew, which may also enhance perceived company support and assist with achieving a better work-life balance.

Objectives: Gold-standard overnight polysomnography does not reliably capture highly variable sleep patterns across the 24-hour day that are common with dementia and often problematic for carers. We evaluated the reliability of automatically scored actigraphy data as an alternative., Methods: Actigraphy recordings were analysed from 15 community-dwelling people with dementia (135 days total) and 14 of their family carers (124 days total). Manual scoring used participant sleep diaries to identify sleep periods. Automated scoring used the manufacturer's algorithm to score entire records., Results: For people with dementia, automated scoring identified more sleep fragmentation at night and increased sleep during the day, with comparable sensitivity but lower specificity than for carers., Conclusions: Automated scoring offers reasonable agreement with manual scoring and may better describe the fragmented nature of dementia-related sleep, which can be challenging to record accurately in a sleep diary. Automated scoring reduces participant burden and could improve research and treatment protocols., (© 2018 AJA Inc.)

In commercial aviation, fatigue is defined as a physiological state of reduced mental or physical performance capability resulting from sleep loss, extended wakefulness, circadian phase, and/or workload. The International Civil Aviation Organisation mandates that responsibility for fatigue risk management is shared between airline management, pilots, and support staff. However, to date, the majority of research relating to fatigue mitigations in long range operations has focused on the mitigations required or recommended by regulators and operators. Little research attention has been paid to the views or operational experience of the pilots who use these (or other) mitigations. This study focused on pilots' views and experiences of in-flight sleep as the primary fatigue mitigation on long range flights. It also sought information about other fatigue mitigation strategies they use. Thematic analysis was used to explore written comments from diary and survey data collected during long range and ultra-long range trips (N = 291 pilots on three different aircraft types, 17 different out-and-back trips, and four airlines based on three continents). The findings indicate that the recommended fatigue mitigation strategies on long-haul flights (particularly in-flight sleep) are effective and well-utilised, consistent with quantitative findings from the same trips. Importantly however, the analyses also highlight areas that require further investigation, including flight preparation strategies in relation to the uncertainty of in-flight break allocation. There were two strategies for sleep prior to a flight: maximising sleep if pilots were expecting later breaks in the flight; or minimising sleep if they were expecting breaks earlier or at unfavourable times in the circadian cycle. They also provide a broader view of the factors that affect the amount and quality of pilots' in-flight sleep, about which evidence has previously been largely anecdotal. The study underscores the value of including the views and experience of pilots in fatigue risk management., Competing Interests: The authors have declared that no competing interests exist.

Background: Many civilian aviation regulators favor evidence-based strategies that go beyond hours-of-service approaches for managing fatigue risk. Several countries now allow operations to be flown outside of flight and duty hour limitations, provided airlines demonstrate an alternative method of compliance that yields safety levels "at least equivalent to" the prescriptive regulations. Here we discuss equivalence testing in occupational fatigue risk management. We present suggested ratios/margins of practical equivalence when comparing operations inside and outside of prescriptive regulations for two common aviation safety performance indicators: total in-flight sleep duration and psychomotor vigilance task reaction speed. Suggested levels of practical equivalence, based on expertise coupled with evidence from field and laboratory studies, are ≤ 30 min in-flight sleep and ± 15% of reference response speed., Methods: Equivalence testing is illustrated in analyses of a within-subjects field study during an out-and-back long-range trip. During both sectors of their trip, 41 pilots were monitored via actigraphy, sleep diary, and top of descent psychomotor vigilance task. Pilots were assigned to take rest breaks in a standard lie-flat bunk on one sector and in a bunk tapered 9 from hip to foot on the other sector., Results: Total in-flight sleep duration (134 ± 53 vs. 135 ± 55 min) and mean reaction speed at top of descent (3.94 ± 0.58 vs. 3.77 ± 0.58) were equivalent after rest in the full vs. tapered bunk., Discussion: Equivalence testing is a complimentary statistical approach to difference testing when comparing levels of fatigue and performance in occupational settings and can be applied in transportation policy decision making.Wu LJ, Gander PH, van den Berg M, Signal TL. Equivalence testing as a tool for fatigue risk management in aviation. Aerosp Med Hum Perform. 2018; 89(4):383-388.

Introduction: Layovers are critical for pilot recovery between flights and minimum layover durations are required by regulation. However, research on the factors affecting layover sleep and safety performance indicators (SPIs) before subsequent flights is relatively sparse. The present project combined data from 6 studies, including 8 long-range and 5 ultra-long range out-and-back trips across a range of different layover destinations (299 pilots in 4-person crews, 410 layovers, 1-3 d layover duration)., Methods: Sleep was monitored via actigraphy from 3 d pre-trip to at least 3 d post-trip. Pilots rated their sleepiness (Karolinska Sleepiness Scale, KSS) and fatigue (Samn-Perelli scale, SP) at duty start for the inbound flight. Mixed model ANOVAs identified independent associations between fatigue and sleepiness SPIs and operational factors (domicile time of duty start for the inbound flight in six 4-h bins, layover duration, and total sleep time (TST) in the 24 h prior to inbound duty start)., Results: TST was greatest on layovers ending between 1200-1559 domicile time (time in the city from which the outbound flight departed) and TST was a significant predictor of both KSS and SP ratings at duty start for the inbound flight., Discussion: TST in the 24 h prior to the inbound flight was greatest when duty start time allowed for the inclusion of a full domicile night time period. In this dataset, circadian end-time of layovers is a key determinant of pilot fatigue status at the beginning of the inbound duty period.Cosgrove J, Wu LJ, van den Berg M, Signal TL, Gander PH. Sleep on long haul layovers and pilot fatigue at the start of the next duty period. Aerosp Med Hum Perform. 2018; 89(1):19-25.

Dementia-related sleep problems can be complex and challenging. Environmental interventions which resynchronise the sleep/wake cycle have been trialled with promising results for people with dementia in institutionalised settings. However, there is less research concerning community-dwelling people with dementia and their family carers. This study involved a five-week feasibility study including timed light therapy, exercise and sleep education. Sleep and physical and mental functioning were measured at the beginning and end of the trial using objective measures, standardised questionnaires and structured participant feedback. Of 15 community-dwelling pairs who participated, nine completed the trial. The case studies presented here reveal that it is feasible for this population to use non-pharmacological interventions, with positive outcomes. However, there are also issues that can mask benefits or prevent compliance. The options for treating dementia are limited. Environmental interventions may help manage dementia-related sleep problems and further trials would be worthwhile to improve compliance and evaluate effectiveness.

Exposure to workplace hazards, such as dust, solvents, and fumes, has the potential to adversely affect the health of people. However, the effects of workplace hazards on health may differ when exposure occurs at different times in the circadian cycle, and among people who work longer hours or who do not obtain adequate sleep. The aim of the present study was to document exposures to workplace hazards across a national sample of New Zealanders, comparing people who work a standard 08:00 -17:00 h Monday-to-Friday working week (Std hours) and those who do not (N-Std hours). New Zealanders (n = 10 000) aged 20-64 yrs were randomly selected from the Electoral Roll to take part in a nationwide survey of workplace exposures. Telephone interviews were conducted between 2004 and 2006, using a six-part questionnaire addressing demographics, detailed information on the current or most recent job (including exposures to a range of workplace hazards), sleep, sleepiness, and health status. N-Std hours were categorised on the basis of: being required to start work prior to 07:00 h or finish work after 21:00 h and/or; having a regular on-call commitment (at least once per week) and/or; working rotating shifts and/or; working night shift(s) in the last month. The response rate was 37% (n = 3003), with 22.2% of participants (n = 656) categorised as working N-Std hours. Industry sectors with the highest numbers of participants working N-Std hours were manufacturing, health and community services, and agriculture, fishing, and forestry. Response rate was 37% (n = 3003) with 22.2% (n = 656) categorised as working N-Std hours. Participants working N-Std hours were more likely to be exposed to all identified hazards, including multiple hazards (OR = 2.45, 95% CI = 2.01-3.0) compared to those working Std hours. Participants working N-Std hours were also more likely to report 'never/rarely' getting enough sleep (OR = 1.38, 95% CI = 1.15-1.65), 'never/rarely' waking refreshed (OR = 1.23, 95% CI = 1.04-1.47), and excessive sleepiness (OR = 1.77, 95% CI = 1.29-2.42). New Zealanders working N-Std hours are more likely to be exposed to hazards in the workplace, to be exposed to multiple hazards, and to report inadequate sleep and excessive sleepiness than their colleagues working a standard 08:00-17:00 h Monday-to-Friday working week. More research is needed on the effects of exposure to hazardous substances outside the usual waking day, on the effects of exposure to multiple hazards, and on the combination of hazard exposure and sleep restriction as a result of shift work.

Objective: Characterize the baseline sleep of long-haul airline pilots., Methods: Sleep of 332 pilots (median age = 51 years, range = 23-64 years) from 4 airlines was measured by actigraphy while at home and off-duty and by retrospective estimate of the total amount of nighttime sleep usually obtained at home., Results: Mean actigraphic sleep per 24 hours during baseline periods was 6.8 hours (SD = 1.0 hour), 52 minutes shorter than mean self-reported usual nighttime sleep (7.6 hours, SD = 1.1 hours)., Conclusions: Pilots' self-reported sleep duration was comparable to weekend sleep of men in general population samples, but their actigraphic baseline sleep was longer than objectively monitored sleep of other samples. Long-haul pilots routinely experience sleep restriction and circadian disruption across trips, both of which are implicated in increased health risks. We recommend that they be educated about the long-term importance for health of obtaining adequate sleep on off-duty days., (Copyright © 2016 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: The aims were: (1) to investigate the independent associations between suboptimal sleep duration and neighborhood deprivation, employment status, self-rated general health, overweight/obesity, and preferred sleep timing (chronotype); and (2) to determine the statistical contribution of socioeconomic, health, and chronotype factors to ethnic inequities in suboptimal sleep duration., Participants: Mail-out survey to a stratified national sample of 5100 Māori (indigenous New Zealanders) and 4000 non-Māori adults (20-59 years) randomly selected from the electoral rolls (54% response rate)., Measurements: Data on usual sleep duration were obtained using a NZ version of the Munich Chronotype Questionnaire. A range of sociodemographic and health-related variables were also available., Results: The prevalence of insufficient (≥2 hours difference in average sleep duration on free days versus scheduled days), short (<7 hours) and long sleep durations (≥9 hours) were consistently higher for Māori than non-Māori. For insufficient sleep, the inequity was partly explained by greater socioeconomic deprivation and more night work among Māori, and further attenuated after adjustment for health-related factors and chronotype. In contrast, ethnic inequities in short and long sleep durations remained, even in the fully adjusted models., Conclusions: Ethnic inequities in insufficient and suboptimal sleep duration narrowed but were not fully explained by differences in socioeconomic position and health status between Māori and non-Māori. Growing evidence suggests that poor sleep may mediate ethnic inequities in other areas of health, therefore, actions that target the basic causes of sleep health inequities should be considered as part of broader population health policies and interventions., (Copyright © 2016 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

Background: This study examined whether subjective measurements of in-flight sleep could be a reliable alternative to actigraphic measurements for monitoring pilot fatigue in a large-scale survey., Methods: Pilots (3-pilot crews) completed a 1-page survey on outbound and inbound long-haul flights crossing 1-7 time zones (N = 586 surveys) between 53 city pairs with 1-d layovers. Across each flight, pilots documented flight start and end times, break times, and in-flight sleep duration and quality if they attempted sleep. They also rated their fatigue (Samn-Perelli Crew Status Check) and sleepiness (Karolinska Sleepiness Scale) at top of descent (TOD). Mixed model ANCOVA was used to identify independent factors associated with sleep duration, quality, and TOD measures. Domicile time was used as a surrogate measure of circadian phase., Results: Sleep duration increased by 10.2 min for every 1-h increase in flight duration. Sleep duration and quality varied by break start time, with significantly more sleep obtained during breaks starting between (domicile) 22:00-01:59 and 02:00-05:59 compared to earlier breaks. Pilots were more fatigued and sleepy at TOD on flights arriving between 02:00-05:59 and 06:00-09:59 domicile time compared to other flights. With every 1-h increase in sleep duration, sleepiness ratings at TOD decreased by 0.6 points and fatigue ratings decreased by 0.4 points., Discussion: The present findings are consistent with previous actigraphic studies, suggesting that self-reported sleep duration is a reliable alternative to actigraphic sleep in this type of study, with use of validated measures, sufficiently large sample sizes, and where fatigue risk is expected to be low. van den Berg MJ, Wu LJ, Gander PH. Subjective measurements of in-flight sleep, circadian variation, and their relationship with fatigue. Aerosp Med Hum Perform. 2016; 87(10):869-875.

Factors contributing to sleep timing and sleep restriction in daily life include chronotype and less flexibility in times available for sleep on scheduled days versus free days. There is some evidence that these two factors interact, with morning types and evening types reporting similar sleep need, but evening types being more likely to accumulate a sleep debt during the week and to have greater sleep extension on weekend nights. The aim of the present study was to evaluate the independent contributions of circadian phase and weekend-to-weekday variability to sleep timing in daily life. The study included 14 morning types and 14 evening types recruited from a community-based sample of New Zealand adults (mean age 41.1 ± 4.7 years). On days 1-15, the participants followed their usual routines in their own homes and daily sleep start, midpoint and end times were determined by actigraphy and sleep diaries. Days 16-17 involved a 17 h modified constant routine protocol in the laboratory (17:00 to 10:00, <20 lux) with half-hourly saliva samples assayed for melatonin. Mixed model ANCOVAs for repeated measures were used to investigate the independent relationships between sleep start and end times (separate models) and age (30-39 years versus 40-49 years), circadian phase [time of the dim light melatonin onset (DLMO)] and weekday/weekend schedules (Sunday-Thursday nights versus Friday-Saturday nights). As expected on weekdays, evening types had later sleep start times (mean = 23:47 versus 22:37, p < .0001) and end times (mean = 07:14 versus 05:56, p < .0001) than morning types. Similarly on weekend days, evening types had later sleep start times (mean = 00:14 versus 23:07, p = .0032) and end times (mean = 08:56 versus 07:04, p < .0001) than morning types. Evening types also had later DLMO (22:06 versus 20:46, p = .0002) than morning types (mean difference = 80.4 min, SE = 18.6 min). The ANCOVA models found that later sleep start times were associated with later DLMO (p = .0172) and weekend-to-weekday sleep timing variability (p < .0001), after controlling for age, while later sleep end times were associated with later DLMO (p = .0038), younger age (p = .0190) and weekend days (p < .0001). Sleep end times showed stronger association with DLMO (for every 30 min delay in DLMO, estimated mean sleep end time occurred 14.0 min later versus 10.19 min later for sleep start times). Sleep end times also showed greater delays on weekends versus weekdays (estimated mean delay for sleep end time = 84 min, for sleep start time = 28 min). Comparing morning types and evening types, the estimated contributions of the DLMO to the mean observed differences in sleep timing were on weekdays, 39% for sleep start times and 49% for sleep end times; and on weekends, 41% for sleep start times and 34% of sleep end times. We conclude that differences in sleep timing between morning types and evening types were much greater than would be predicted on the basis of the independent contribution of the difference in DLMO on both weekdays and weekend days. The timing of sleep in daily life involves complex interactions between physiological and psychosocial factors, which may be moderated by age in adults aged 30-49 years.

Background: The aims of this study were to monitor cabin crew fatigue, sleep, and performance on an ultra-long range (ULR) trip and to evaluate the appropriateness of applying data collection methods developed for flight crew to cabin crew operations under a fatigue risk management system (FRMS)., Methods: Prior to, throughout, and following the ULR trip (outbound flight ULR; mean layover duration=52.6 h; inbound flight long range), 55 cabin crew (29 women; mean age 36.5 yr; 25 men; mean age 36.6 yr; one missing data) completed a sleep/duty diary and wore an actigraph. Across each flight, crewmembers rated their fatigue (Samn-Perelli Crew Status Check) and sleepiness (Karolinska Sleepiness Scale) and completed a 5-min Psychomotor Vigilance Task (PVT) at key times., Results: Of crewmembers approached, 73% (N=134) agreed to participate and 41% (N=55) provided data of suitable quality for analysis. In the 24 h before departure, sleep averaged 7.0 h and 40% took a preflight nap. All crewmembers slept in flight (mean total sleep time=3.6 h outbound, 2.9 h inbound). Sleepiness and fatigue were lower, and performance better, on the longer outbound flight than on the inbound flight. Post-trip, crewmembers slept more on day 1 (mean=7.9 h) compared to baseline days, but there was no difference from day 2 onwards., Discussion: The present study demonstrates that cabin crew fatigue can be managed effectively on a ULR flight and that FRMS data collection is feasible for cabin crew, but operational differences between cabin crew and flight crew need to be considered.

The Karolinska Sleepiness Scale and Samn-Perelli fatigue ratings, and psychomotor vigilance task performance are proposed as measures for monitoring commercial pilot fatigue. In laboratory studies, they are sensitive to sleep/wake history and circadian phase. The present analyses examined whether they reliably reflect sleep/wake history and circadian phase during transmeridian flight operations. Data were combined from four studies (237 pilots, 730 out-and-back flights between 13 city pairs, 1-3-day layovers). Sleep was monitored (wrist actigraphy, logbooks) before, during and after trips. On duty days, sleepiness, fatigue and mean response speed were measured pre-flight and at the top of the descent. Mixed-model analysis of variance examined associations between these measures and sleep/wake history, after controlling for operational factors. Circadian phase was approximated by local (domicile) time in the city where each trip began and ended. More sleep in the 24 h prior to duty was associated with lower pre-flight sleepiness and fatigue and faster response speed. Sleepiness and fatigue were greater before flights departing during the domicile night and early morning. At the top of the descent, pilots felt less sleepy and fatigued after more in-flight sleep and less time awake. Flights arriving in the early-mid-morning (domicile time) had greater sleepiness and fatigue and slower response speeds than flights arriving later. Subjective ratings showed expected associations with sleep/wake history and circadian phase. The response speed showed expected circadian variation but was not associated with sleep/wake history at the top of the descent. This may reflect moderate levels of fatigue at this time and/or atypically fast responses among pilots., (© 2014 European Sleep Research Society.)

Background: This study examined the uptake and effectiveness of fatigue mitigation guidance material including sleep recommendations for a trip with a westward ultra-long-range flight and return long-range flight., Methods: There were 52 flight crew (4-pilot crews, mean age 55 yr) who completed a sleep/duty diary and wore an actigraph prior to, during, and after the trip. Primary crew flew the takeoff and landing, while relief crew flew the aircraft during the Primary crew's breaks. At key times in flight, crewmembers rated their fatigue (Samn-Perelli fatigue scale) and sleepiness (Karolinska Sleepiness Scale) and completed a 5-min Psychomotor Vigilance Task., Results: Napping was common prior to the outbound flight (54%) and did not affect the quantity or quality of in-flight sleep (mean 4.3 h). Primary crew obtained a similar amount on the inbound flight (mean 4.0 h), but Secondary crew had less sleep (mean 2.9 h). Subjective fatigue and sleepiness increased and performance slowed across flights. Performance was faster on the outbound than inbound flight. On both flights, Primary crew were less fatigued and sleepy than Secondary crew, particularly at top of descent and after landing. Crewmembers slept more frequently and had more sleep in the first 24 h of the layover than the last, and had shifted their main sleep to the local night by the second night., Discussion: The suggested sleep mitigations were employed by the majority of crewmembers. Fatigue levels were no worse on the outbound ultra-long-range flight than on the return long-range flight.

Introduction: Flight timing is expected to influence pilot fatigue because it determines the part of the circadian body clock cycle that is traversed during a flight. However the effects of flight timing are not well-characterized because field studies typically focus on specific flights with a limited range of departure times and have small sample sizes. The present project combined data from four studies, including 13 long-range and ultra-long range out-and-back trips across a range of departure and arrival times (237 pilots in 4-person crews, 730 flight segments, 1-3 d layovers)., Methods: All studies had tripartite support and underwent independent ethical review. Sleep was monitored (actigraphy) from 3 d prior to ≥ 3 d post-trip. Preflight and at top of descent (TOD), pilots rated their sleepiness (Karolinska Sleepiness Scale) and fatigue (Samn-Perelli scale), and completed a psychomotor vigilance task (PVT) test. Mixed model ANOVA identified independent associations between fatigue measures and operational factors (domicile times of departure and arrival, flight duration and direction, landing versus relief crew)., Results: Preflight subjective fatigue and sleepiness were lowest for flights departing 14:00-17:59. Total in-flight sleep was longest on flights departing 18:00-01:59. At TOD, fatigue and sleepiness were higher and PVT response speeds were slower on flights arriving 06:00-09:59 than on flights arriving later. PVT response speed at TOD was also faster on longer flights., Discussion: The findings indicate the influence of flight timing (interacting with the circadian body clock cycle), as well as flight duration, on in-flight sleep and fatigue measures at TOD.

The aim was to estimate the prevalence of, and identify independent risk factors for, Advanced (ASPD) and Delayed Sleep Phase Disorder (DSPD) among Māori (indigenous New Zealanders) and non-Māori adults using a self-report questionnaire. The Munich Chronotype Questionnaire was mailed to a stratified sample of 9100 adults (5100 Māori and 4000 non-Māori) aged 20-59 years randomly selected from the electoral rolls (54% response rate). Different definitions for ASPD and DSPD were developed using combinations of symptoms including self-reported bed and rising times, current chronotype, and a desire to change sleep schedule. Logistic regression models were used to model the likelihood of reporting ASPD or DSPD separately after adjusting for ethnicity (Māori versus non-Māori), sex (males versus females), age (in decades), socio-economic deprivation (NZDep2006 deciles) and employment status (unemployed, night work versus employed with no night work). The prevalence of ASPD ranged from 0.25% to 7.13% whereas the prevalence of DSPD was 1.51 to 8.90% depending on the definition used. The prevalence of ASPD was higher among men and increased with age. The prevalence of DSPD was higher among those living in more deprived areas and decreased with age. After controlling for ethnicity, gender, age, socio-economic deprivation and employment status, people with ASPD were more likely to report excessive daytime sleepiness, whereas those with DSPD were more likely to report poor or fair self-rated health. Reporting ASPD and DSPD were associated with self-reported night work. In this large sleep timing survey, we found no differences in the prevalence of self-identified ASPD and DSPD between Maori and non-Maori. This has implications for the development and provision of sleep health services and strategies for managing the significant impact of work patterns on sleep.

Sleep disturbances are common with dementia and can adversely affect waking function. However, the perspectives of people with dementia and their family caregivers concerning their sleep are under-researched. We conducted three focus groups with 12 community-dwelling pairs (a person with dementia and their family caregiver). Discussions addressed sleep disturbances, coping strategies, and beliefs and attitudes surrounding sleep. Thematic analysis indicated that dementia-related sleep disturbances were common, including confused awakenings and dementia-related behaviors at night, changes to sleep timing, and nightmares. Common issues for caregivers included being woken at night, having problems getting back to sleep, trips to the bathroom, and daytime sleepiness. Participants often normalized their sleeping problems and had developed a number of coping strategies. These findings highlight the impact that sleep disturbances can have on people living with dementia. Their experiences and beliefs need to be considered for developing effective interventions to improve sleep, waking function, and wellbeing.

Introduction: Implementation of Fatigue Risk Management Systems (FRMS) is gaining momentum; however, agreed safety performance indicators (SPIs) are lacking. This paper proposes an initial set of SPIs based on measures of crewmember sleep, performance, and subjective fatigue and sleepiness, together with methods for interpreting them., Methods: Data were included from 133 landing crewmembers on 2 long-range and 3 ultra-long-range trips (4-person crews, 3 airlines, 220 flights). Studies had airline, labor, and regulatory support, and underwent independent ethical review. SPIs evaluated preflight and at top of descent (TOD) were: total sleep in the prior 24 h and time awake at duty start and at TOD (actigraphy); subjective sleepiness (Karolinska Sleepiness Scale) and fatigue (Samn-Perelli scale); and psychomotor vigilance task (PVT) performance. Kruskal-Wallis nonparametric ANOVA with post hoc tests was used to identify significant differences between flights for each SPI., Results: Visual and preliminary quantitative comparisons of SPIs between flights were made using box plots and bar graphs. Statistical analyses identified significant differences between flights across a range of SPls., Discussion: In an FRMS, crew fatigue SPIs are envisaged as a decision aid alongside operational SPIs, which need to reflect the relevant causes of fatigue in different operations. We advocate comparing multiple SPIs between flights rather than defining safe/unsafe thresholds on individual SPIs. More comprehensive data sets are needed to identify the operational and biological factors contributing to the differences between flights reported here. Global sharing of an agreed core set of SPIs would greatly facilitate implementation and improvement of FRMS.

This study evaluated whether pilot fatigue was greater on ultra-long range (ULR) trips (flights >16 h on 10% of trips in a 90-day period) than on long range (LR) trips. The within-subjects design controlled for crew complement, pattern of in-flight breaks, flight direction and departure time. Thirty male Captains (mean age = 54.5 years) and 40 male First officers (mean age = 48.0 years) were monitored on commercial passenger flights (Boeing 777 aircraft). Sleep was monitored (actigraphy, duty/sleep diaries) from 3 days before the first study trip to 3 days after the second study trip. Karolinska Sleepiness Scale, Samn-Perelli fatigue ratings and a 5-min Psychomotor Vigilance Task were completed before, during and after every flight. Total sleep in the 24 h before outbound flights and before inbound flights after 2-day layovers was comparable for ULR and LR flights. All pilots slept on all flights. For each additional hour of flight time, they obtained an estimated additional 12.3 min of sleep. Estimated mean total sleep was longer on ULR flights (3 h 53 min) than LR flights (3 h 15 min; P(F) = 0.0004). Sleepiness ratings were lower and mean reaction speed was faster at the end of ULR flights. Findings suggest that additional in-flight sleep mitigated fatigue effectively on longer flights. Further research is needed to clarify the contributions to fatigue of in-flight sleep versus time awake at top of descent. The study design was limited to eastward outbound flights with two Captains and two First Officers. Caution must be exercised when extrapolating to different operations., (© 2013 European Sleep Research Society.)

Study Objectives: To assess the amount and quality of sleep that flight crew are able to obtain during flight, and identify factors that influence the sleep obtained., Design: Flight crew operating flights between Everett, WA, USA and Asia had their sleep recorded polysomnographically for 1 night in a layover hotel and during a 7-h in-flight rest opportunity on flights averaging 15.7 h., Setting: Layover hotel and in-flight crew rest facilities onboard the Boeing 777-200ER aircraft., Participants: Twenty-one male flight crew (11 Captains, mean age 48 yr and 10 First Officers, mean age 35 yr)., Interventions: N/A., Measurements and Results: Sleep was recorded using actigraphy during the entire tour of duty, and polysomnographically in a layover hotel and during the flight. Mixed model analysis of covariance was used to determine the factors affecting in-flight sleep. In-flight sleep was less efficient (70% vs. 88%), with more nonrapid eye movement Stage 1/Stage 2 and more frequent awakenings per h (7.7/h vs. 4.6/h) than sleep in the layover hotel. In-flight sleep included very little slow wave sleep (median 0.5%). Less time was spent trying to sleep and less sleep was obtained when sleep opportunities occurred during the first half of the flight. Multivariate analyses suggest age is the most consistent factor affecting in-flight sleep duration and quality., Conclusions: This study confirms that even during long sleep opportunities, in-flight sleep is of poorer quality than sleep on the ground. With longer flight times, the quality and recuperative value of in-flight sleep is increasingly important for flight safety. Because the age limit for flight crew is being challenged, the consequences of age adversely affecting sleep quantity and quality need to be evaluated.

Shiftwork and work-hour limits for junior doctors are now well established in hospital work patterns. In order to ensure that trainees have adequate exposure to daytime elective surgical procedures, there is a tendency to have long shifts that include an after-hours component. However, long shifts can cause performance decrement due to time-on-task fatigue. In addition, shifts that encroach upon sleep time result in sleep loss. Using a high-fidelity patient simulation environment, we undertook a randomised, controlled trial to examine fatigue effects. A within-subjects comparison was used to evaluate the effect of 15-hour day shifts on the performance of 12 anaesthesia registrars. Preoperative assessment, machine check and taskwork using 42 task categories were evaluated. In both conditions, there was failure to meet current guidelines for preoperative evaluation or machine check, and when fatigued there was a 'trend' (P=0.06) to a reduction in the number of items in the machine check. With increase in time awake, there was an increase in time taken for explanation to the patient, an increase in mean duration of explanation to the patient, more time looking at the intravenous line or fluids when multi-tasking but less time adjusting the intravenous fluid. These effects are minor during routine uncomplicated induction of anaesthesia, but further investigation is needed to examine fatigue effects during non-routine circumstances.

Operational settings involving shiftwork or extended operations require periods of prolonged wakefulness, which in conjunction with sleep loss and circadian factors, can have a negative impact on performance, alertness, and workplace safety. Napping has been shown to improve performance and alertness after periods of prolonged wakefulness and sleep loss. Longer naps may not only result in longer-lasting benefits but also increase the risk of sleep inertia immediately upon waking. The time course of performance after naps of differing durations is thus an important consideration in weighing the benefits and risks of napping in workplace settings. The objective of this study was to evaluate the effectiveness of nap opportunities of 20, 40, or 60 min for maintaining alertness and performance 1.5-6 h post-nap in simulated nightwork (P1) or extended operations (P2). Each protocol included 12 participants in a within-subjects design in a controlled laboratory environment. After a baseline 8 h time-in-bed, healthy young males (P1 mean age 25.1 yr; P2 mean age 23.2 yr) underwent either ≈ 20 h (P1) or ≈ 30 h (P2) of sleep deprivation on four separate occasions, followed by nap opportunities of 0, 20, 40, and 60 min. Sleep on the baseline night and during the naps was recorded polysomnographically. During the nap opportunities, sleep onset latency was short and sleep efficiency was high. A greater proportion of slow-wave sleep (SWS) was obtained in nap opportunities of 40 and 60 min compared with 20 min. Rapid eye movement (REM) sleep occurred infrequently. A subjective sleepiness rating (Karolinska Sleepiness Scale, KSS), 2-Back Working Memory Task (WMT), and Psychomotor Vigilance Task (PVT) were completed 1.5, 2, 2.5, 3, 4, 5, and 6 h post-nap. The slowest 10% of PVT responses were significantly faster after 40 and 60 min naps compared with a 20 min (P1) or no (P2) nap. There were significantly fewer PVT lapses after 40 and 60 min naps compared with no nap (P2), and after 60 min naps compared with 20 min naps (P1). Participants felt significantly less sleepy and made more correct responses and fewer omissions on the WMT after 60 min naps compared with no nap (P2). Subjective sleepiness and WMT performance were not related to the amount of nap-time spent in SWS. However, PVT response speed was significantly slower when time in SWS was <10 min compared with 20-29.9 min. In conclusion, in operationally relevant scenarios, nap opportunities of 40 and 60 min show more prolonged benefits 1.5-6 h post-nap, than a 20 min or no nap opportunity. Benefits were more apparent when the homeostatic pressure for sleep was high and post-nap performance testing occurred across the afternoon (P2). For sustained improvement in cognitive performance, naps of 40-60 min are recommended.

Due to the mixed findings of previous studies, it is still difficult to provide guidance on how to best manage sleep inertia after waking from naps in operational settings. One of the few factors that can be manipulated is the duration of the nap opportunity. The aim of the present study was to investigate the magnitude and time course of sleep inertia after waking from short (20-, 40- or 60-min) naps during simulated night work and extended operations. In addition, the effect of sleep stage on awakening and duration of slow wave sleep (SWS) on sleep inertia was assessed. Two within-subject protocols were conducted in a controlled laboratory setting. Twenty-four healthy young men (Protocol 1: n = 12, mean age = 25.1 yrs; Protocol 2: n = 12, mean age = 23.2 yrs) were provided with nap opportunities of 20-, 40-, and 60-min (and a control condition of no nap) ending at 02:00 h after ∼20 h of wakefulness (Protocol 1 [P1]: simulated night work) or ending at 12:00 h after ∼30 h of wakefulness (Protocol 2 [P2]: simulated extended operations). A 6-min test battery, including the Karolinska Sleepiness Scale (KSS) and the 4-min 2-Back Working Memory Task (WMT), was repeated every 15 min the first hour after waking. Nap sleep was recorded polysomnographically, and in all nap opportunities sleep onset latency was short and sleep efficiency high. Mixed-model analyses of variance (ANOVA) for repeated measures were calculated and included the factors time (time post-nap), nap opportunity (duration of nap provided), order (order in which the four protocols were completed), and the interaction of these terms. Results showed no test x nap opportunity effect (i.e., no effect of sleep inertia) on KSS. However, WMT performance was impaired (slower reaction time, fewer correct responses, and increased omissions) on the first test post-nap, primarily after a 40- or 60-min nap. In P2 only, performance improvement was evident 45 min post-awakening for naps of 40 min or more. In ANOVAs where sleep stage on awakening was included, the test x nap opportunity interaction was significant, but differences were between wake and non-REM Stage 1/Stage 2 or wake and SWS. A further series of ANOVAs showed no effect of the duration of SWS on sleep inertia. The results of this study demonstrate that no more than 15 min is required for performance decrements due to sleep inertia to dissipate after nap opportunities of 60 min or less, but subjective sleepiness is not a reliable indicator of this effect. Under conditions where sleep is short, these findings also suggest that SWS, per se, does not contribute to more severe sleep inertia. When wakefulness is extended and napping occurs at midday (i.e., P2), nap opportunities of 40- and 60-min have the advantage over shorter duration sleep periods, as they result in performance benefits ∼45 min after waking.

Aim: To understand declining response rates in New Zealand sleep health surveys by examining contextual changes and specific aspects of the questionnaires and research design that may have contributed., Method: From 1999-2008, four population surveys were undertaken, seeking to recruit equal numbers of Māori and non-Māori, consistent with the Kaupapa Māori principle of equal explanatory power; using the electoral roll as a sampling frame and including extensive follow-up., Results: In successive surveys, there were fewer respondents in all age groups. Response rates from Māori were lower in all surveys and the percentage decline was greater than for non-Māori. Between 1999 and 2008, the response rates from the initial mail-out decreased by 50% and the proportion of the sample that were uncontactable increased by 50%. Identified societal trends included decreased currency of electoral roll address information, declining use of listed landline telephone numbers, and possibly declining willingness to participate from increasing respondent burden. Contributing study design features may have included changes in Māori leadership, increasing complexity of questions and saliency of the research topic to potential participants., Conclusions: The declining response rate in sleep population surveys is likely to be due to a number of factors. The pros and cons of using the electoral roll as a sampling frame in mail surveys should be carefully considered.

Aim: To examine the attitudes of taxi drivers towards symptoms of obstructive sleep apnoea syndrome (OSAS), and to determine whether these attitudes could influence their health and safety as a professional driver., Method: Qualitative research based on three focus groups conducted in Wellington, New Zealand. Participants were 27 taxi drivers who had a high pre-test risk for obstructive sleep apnoea. Assignment to focus groups was based on self-identification as being Maori and Pacific peoples, New Zealand European, or non-Maori and non-Pacific., Result: Participants described avoidance of health issues and dissatisfaction with their general practitioners. These attitudes were attributable to: (i) lack of knowledge, (ii) deliberate avoidance, and (iii) fear of loss of employment and income., Conclusions: The attitudes and level of knowledge of the focus group participants lead us to make the following recommendations. Drivers need systematic education about the effects of insufficient sleep and of OSAS on driving skills and safety. Taxi managers and drivers should cooperate to develop and implement safe driving policies to manage driver fatigue. Clear guidelines are need for drivers, managers, and healthcare professionals on the diagnosis and treatment of sleep disorders among drivers, and their potential consequences for driver licensing.

Introduction: Crewmembers on ultra long-range commercial flights have the opportunity for rest and sleep in onboard areas in which the barometric pressure is 75.3 kPa (565 mmHg) or higher, equivalent to a terrestrial altitude of 2438 m (8000 ft) or lower. Sleep at higher altitudes is known to be disturbed, resulting in postsleep neurobehavioral performance decrements. We investigated the effects of sleep at 2438 m on oxygen saturation, heart rate, sleep quantity, sleep quality, postsleep neurobehavioral performance, and mood., Methods: Twenty men, 30-56 yr of age, participated in a blinded cross-over investigation conducted in a hypobaric chamber to compare the effects of sleep at altitude (ALT, 2438 m) and ground level (GND, 305 m)., Results: SpO2 measured before sleep was significantly lower at ALT than at GND, 90.7 +/- 2.0% (average +/- SD) and 96.2 +/- 2.0%, respectively. During sleep, SpO2 decreased further to 86.1 +/- 2.0% at ALT, and 92.3% +/- 2.0% at GND. The percent of time during which SpO2 was below 90% was 44.4% (3.6-86.9%) at ALT and 0.1% (0.0-22.9%) at GND. Objective and subjective measurements of sleep quantity and quality did not differ significantly with altitude, nor did postsleep neurobehavioral performance or mood., Discussion: The absence of significant changes in sleep and post-sleep neurobehavioral performance associated with pronounced oxygen desaturation during sleep was unexpected. Further study is needed to determine if the same effects occur in women and to characterize the changes in respiratory physiology that occur during sleep at 2438 m in both sexes.

Purpose: This study aimed to describe the distribution of risk factors for obstructive sleep apnoea syndrome (OSAS) among taxi drivers, and to investigate differences by ethnicity in OSAS symptoms among drivers., Methods: A two-page postal questionnaire was completed by 241 professional taxi drivers from Wellington, New Zealand. Obstructive sleep apnoea syndrome was defined as having an estimated 15 or more respiratory disturbances, per hour of sleep (Respiratory Disturbance Index (RDI)> or =15) and self-reported daytime sleepiness., Results: Pacific and Māori taxi drivers were more likely to have symptoms and risk factors for OSAS, compared to non-Māori non-Pacific drivers. In particular, Pacific drivers had a significantly increased pre-test probability of having moderate-severe OSA (RDI> or =15)., Conclusions: Some professional taxi drivers are at increased risk for moderate-severe OSAS, especially Pacific and Māori taxi drivers. Untreated OSAS increases motor vehicle crash risk, so these findings have implications for the health and safety of drivers and their passengers. They suggest a need for more comprehensive research to guide policy on medical examinations required for licensing professional drivers as fit to drive.

The aims of this study were to measure sleep during a planned nap on the night shift; and to use objective measures of performance and alertness to compare the effects of the nap opportunity versus staying awake. Twenty-eight air traffic controllers (mean age 36 years, nine women) completed four night shifts (two with early starts and two with late starts). Each type of night shift (early/late start) included a 40-min planned nap opportunity on one occasion and no nap on the other. Polysomnographic data were used to measure sleep and waking alertness [spectral power in the electroencephalogram (EEG) during the last hour of the night shift and the occurrence of slow rolling eye movements (SEMs) subsequent to the nap]. Psychomotor performance task [Psychomotor Vigilance Task (PVT)] was completed at the beginning and end of the shift, and after the nap (or an equivalent time if no nap was taken). Nap sleep latencies were relatively long (mean = 19 min) and total sleep time short (mean = 18 min), with minimal slow wave sleep (SWS, mean = 0%), and no rapid eye movement sleep. Nap sleep resulted in improved PVT performance (mean and slowest 10% of reaction time events), decreased spectral power in the EEG and reduced the likelihood of SEMs. The occurrence of SWS in the nap decreased spectral power in the EEG. This study indicates that although sleep taken at work is likely to be short and of poor quality it still results in an improvement in objective measures of alertness and performance.

Since 1995, air transport operators in New Zealand have been able to meet the flight and duty time (FDT) regulations by operating according to prescriptive FDT limits or by seeking approval to operate under a potentially more flexible company-specific FDT scheme. There has been no formal assessment of the impact of this increased flexibility on fatigue management processes. The aim of the present study was to determine the strategies and processes that commercial aircraft operators in New Zealand have in place for managing fatigue and whether these differed according to the type of FDT system under which organizations were operating. All air transport operators in New Zealand were sent questionnaires that were to be completed by an individual in a management role, a line pilot, and an individual in a rostering role. Questions were asked about the FDT system under which the organization operated, the strategies and processes in place for managing fatigue, and the consequences of the organization's approach to managing fatigue. One hundred and fifty-three responses were received from 88 organizations (55% of all air operators) and were representative of the structure of the New Zealand industry. Air operators were most likely to report that they monitored flight and duty times and pilot workload to manage fatigue (used by 90-99% and 70-90%, respectively), while educating rostering staff and reviewing the processes for managing fatigue were the least utilized strategies (used by 36-50% and 39-60%, respectively). Within the same organization, managers were more likely than line pilots to report the use of specific fatigue management strategies. There were no differences found between organizations operating under prescriptive regulations and those using a company-specific scheme on ratings of how well fatigue was managed, the number of fatigue management strategies employed, or the frequency of use of selected strategies. Across the industry as a whole, the provision of more flexible regulatory options has not greatly changed fatigue management practices, although some operators have implemented innovative strategies. The findings suggest a need to raise the level of knowledge within the industry regarding the causes and consequences of fatigue and of processes for its management. This is further supported by the discrepancies between the responses of line pilots and managers, which raise doubts about the effectiveness of some strategies nominally being employed. The regulator and other relevant industry groups should consider how to move the industry toward a mature safety culture and solid knowledge base because these are fundamental to more flexible fatigue management regimes, as is adequate regulatory knowledge, support, and oversight.

Introduction: In Air Traffic Control, counterclockwise rapidly rotating shift schedules are often employed but may result in significant sleep loss. This has potential consequences for performance, particularly if a night shift is worked. As part of a large-scale field study, the pattern of sleep across a 4-d counterclockwise, rapidly rotating schedule (afternoon, day, morning, night shift) was documented and relationships between prior sleep and performance during the night shift were investigated., Methods: There were 28 controllers who completed 4 periods of data collection which included 2 d before and 2 d after a 4-d shift cycle. Sleep was recorded using an actigraph and sleep diary, and performance on each night shift was measured three times using the Psychomotor Vigilance Task., Results: Across the work week, sleep duration decreased largely due to earlier rise times associated with shift start times moving backward. In the short turn-around between the morning and night shift, 90% of controllers slept for an average of 2.2 h. Improved performance on the night shift was related only to longer periods of sleep the night prior., Discussion: This study demonstrates that a 4-d counterclockwise, rapidly rotating schedule results in a progressive reduction in sleep and consequently the rapid accumulation of a sleep debt. To help maintain their performance on the night shift, it is recommended that controllers attempt to obtain at least 6 h sleep the night before a night shift. It is also recommended that ATC providers educate their workforce about this issue.

Objective: This study assessed the effect of removing artifacts from workplace electroencephalography (EEG) recordings on power spectra and the consequent interpretation of changes in alertness., Methods: EEG was recorded for 27 air traffic controllers on the night shifts of four roster cycles. On two of the four night shifts, each controller was given a 40-minute opportunity to nap, while on the other two they remained awake (105 shifts in total). Recordings for the last hour of each night shift were screened for artifacts by an experienced viewer (who viewed the EEG in isolation from other electrophysiological recordings). The effects of the nap opportunity on the EEG power spectra were then analyzed in a mixed model analysis of variance in the presence and absence of artifact-contaminated data., Results: Overall, 89.3% of the EEG recordings contained artifacts. Removal of these data markedly altered the interpretation of how the nap opportunities affected the EEG power spectra. The spectral parameters of the artifact appeared to be different when the participants were given the opportunity to nap., Conclusions: Removal of artifacts can dramatically affect the interpretation of workplace EEG recordings. This potential source of error is often unreported.

Background: Obstructive sleep apnoea syndrome (OSAS) affects an estimated 2-4% of the middle aged population. Meta-analyses of randomised controlled trials have shown that the severe presentation of the syndrome (apnoea hypopnoea index (AHI) >30/hour) is effectively treated with continuous positive airway pressure (CPAP). Until recently there have been insufficient data to determine whether CPAP improves sleepiness in the larger subgroup with mild to moderate OSAS (AHI 5-30/hour)., Methods: A systematic search of Medline and a hand search identified seven randomised controlled trials where CPAP was compared with either a placebo or with conservative management in the treatment of mild to moderate OSAS (AHI 5-30/hour). All trials used the Epworth Sleepiness Scale (ESS), four used the Multiple Sleep Latency Test (MSLT), and three used the Maintenance of Wakefulness Test (MWT) to measure sleepiness., Results: Meta-analyses indicated that CPAP significantly reduced subjective daytime sleepiness (ESS) by 1.2 points (95% CI 0.5 to 1.9, p = 0.001), improved objective daytime wakefulness (MWT) by 2.1 minutes (95% CI 0.5 to 3.7, p = 0.011), but did not affect objective daytime sleepiness (MSLT, mean benefit -0.2 minutes, 95% CI -1.0 to 0.6, p = 0.6). The two significant effects were small (effect size <0.30)., Conclusions: CPAP elicits small improvements in subjective sleepiness and objective wakefulness in people with mild to moderate OSAS. However, the effects on sleepiness are of limited clinical significance.

The Horne and Ostberg Morningness/Eveningness Questionnaire (MEQ) is widely used to differentiate between morning and evening types, but there is very little epidemiological evidence about the distribution of MEQ chronotypes in the general population. The purpose of the present study was to simultaneously investigate the influence of demographic, socioeconomic, and work factors on the distribution of morningness/eveningness. A New Zealand version of the MEQ was mailed to 5000 New Zealand adults, ages 30 to 49 years, who were randomly selected from the electoral rolls (55.7% response rate). A total of 2526 questionnaires were included in the analyses. According to the Horne and Ostberg classification, 49.8% of the total population was classified as morning type compared to 5.6% having an evening-type preference. However, using new cutoffs for middle-aged working adults described by Taillard et al. (2004), 24.7% of the population was morning type and 26.4% was evening type. After controlling for ethnicity, gender, and socioeconomic deprivation, participants ages 30 to 34 years were more likely to be definitely evening type (odds ratio [OR] = 1.59, p < 0.05) and less likely to be morning type (moderately morning type, OR = 0.59, p < 0.01, or definitely morning type, OR = 0.59, p < 0.05) compared to those ages 45 to 49 years. Work schedules were also important predictors of chronotype, with night workers more likely to be definitely evening type (OR = 1.49, p = 0.05) and the unemployed less likely to be moderately morning type (OR = 0.64, p < 0.05) compared to other workers. Evening types were 2.5 times more likely to report that their general health was only poor or fair compared to morning types (p < 0.01). This study confirms that the original criteria of Horne and Ostberg (1976) are not useful for classifying chronotypes in a middle-aged population. The authors conclude that morningness/eveningness preference is largely independent of ethnicity, gender, and socioeconomic position, indicating that it is a stable characteristic that may be better explained by endogenous factors.

Introduction: Flight crew sleep is recognized as critical to alertness and safety, but few studies have compared the reliability of the different types of sleep monitoring that are commonly used. The present study compared actigraphic and subjective estimates of sleep to the gold standard, polysomnography (PSG)., Methods: In-flight (25 episodes) and layover sleep (21 episodes) of 21 flight crew were measured with PSG and actigraphy. Subjective reports were made 30 min after in-flight sleep episodes. Actigraphy data were analyzed at low, medium, and high activity thresholds., Results: Actigraphic and subjective estimates of sleep duration correlated highly with PSG (range 0.84-0.95), regardless of sleep location or activity threshold. Mean differences were relatively small (-36-20 min), but the 95% confidence intervals of the differences were wide (+/- 71- +/- 103 min), particularly for subjective estimates (+/- 112 min). Actigraphic estimates of sleep efficiency and latency showed moderate to poor correlation with PSG values. Epoch-by-epoch comparisons showed the actigraph was sensitive to sleep (83-95%), but not very specific (34-62%). Kappa values indicated only weak agreement (< 0.4)., Discussion: For estimating mean sleep duration, both actigraphic and subjective estimates are sufficiently close to PSG values, but the amount of random error must be considered. Any single estimate may vary by more than 1 h from the mean difference. Neither actigraphy nor subjective estimates are suitable for estimating sleep efficiency and latency. Findings indicate that the performance of the actigraph is not altered in flight, other than the predictable effects associated with shorter, more disturbed sleep.

Objective: To investigate the prevalence of self-reported insomnia symptoms among Maori (Indigenous people) and non-Maori adults in the general population of New Zealand. To explore the consequences for health and quality of life experienced by those who report common insomnia complaints and sleeping problems., Methods: In 2001, a two-page questionnaire was mailed to a stratified random sample of 4,000 adults aged 20-59 years nationwide. Participants were selected from the New Zealand electoral roll. The sample design aimed for equal numbers of Maori and non-Maori participants, men and women, and participants in each decade of age (72.5% response rate)., Results: Population prevalence estimates indicate that self-reported insomnia symptoms and sleeping problems are higher among Maori than non-Maori. Multiple logistic regression analyses showed that self-reported insomnia symptoms and/or sleeping problems are significantly associated with reporting poor or fair health and quality of life outcomes., Conclusions: Approximately one-quarter of adults in New Zealand may suffer from a chronic sleep problem, highlighting insomnia as a major public health issue in New Zealand., Implications: Significant differences in the prevalence of insomnia symptoms and current sleeping problems with respect to ethnicity have implications in the purchase and development of treatment services, with greater need for these services among Maori than non-Maori.

Objective: To assess the role of sleep-related factors, ethnicity and socioeconomic deprivation in self-reported motor vehicle accidents while driving, after controlling for gender, age and driving exposure., Methods: Mail survey to a random electoral roll sample of 10,000 people aged 30-60 years, stratified by age decades and ethnicity (71% response rate). The analytical sample included 5,534 current drivers (21.6% Maori men, 21.2% Maori women, 30% non-Maori men, 27.2% non-Maori women)., Results: Multiple logistic regression analyses revealed the following independent risk factors for accident involvement while driving (last three years): being younger; higher average weekly driving hours; never/rarely getting enough sleep (OR=1.26, 95% CI 1.06-1.49); reporting any chance of dozing in a car while stopped in traffic (Epworth Sleepiness Scale question 8, OR=1.52, 95% CI 1.15-2.02); and among women, being non-Maori. Total Epworth score was not significantly related to reported accident involvement., Conclusions: Chronic sleep restriction, and any likelihood of dozing off at the wheel of a motor vehicle, were significant independent predictors of self-reported involvement in all types of motor vehicle accidents, not only those identified as fatigue-related. The Epworth Sleepiness Scale alone is not a reliable clinical tool for identifying individuals at higher risk of crashes., Implications: Factors relating to chronic sleepiness were as important as established demographic risk factors for self-reported motor vehicle accident involvement among 30-60 year-old drivers. The findings reinforce the need for multi-faceted campaigns to reduce sleepy driving.

Fifteen anaesthetists were observed while providing anaesthesia for 15 pairs of adult cardiac surgical operations, using conventional methods for one of each pair and a new drug administration system designed to reduce error for the other. Aspects of each method were rated by users on 10-cm visual analogue scales (10 being best). The new system was rated more favourably than conventional methods in terms of safety (median [range] = 8.1 [6.8-9.7] vs. 7.1 [2.6-9.3] cm; p = 0.001) and usability (8.5 [5.9-9.4] vs. 7.5 [3.2-9.8] cm; p=0.027). The new system saved preparation time both before anaesthesia (median [range] = 180 [32-480] vs. 360 [120-600] s; p=0.013) and during anaesthesia (10 [2-38] vs. 12 [10-60] s; p=0.009). Prefilled syringes for the new system increased costs by euro 23.00 per anaesthetic (p = 0.041), but this increase is likely to be offset by the potential of the new system to decrease costly iatrogenic harm by preventing drug error.

Patients with osteoarthritis commonly complain of sleep disturbance that may be due to pain. Osteoarthritic hip pain is commonly alleviated by total hip arthroplasty (THA). Forty-eight patients waiting for THA completed a sleep questionnaire and were monitored using actigraphy and sleep diaries for 4 to 5 nights, 1 month before and 3 months after surgery. For the group as a whole, significant improvements were seen in subjective and objective measures of sleep after THA. In this study, 75% of participants reported that their sleep was never or rarely disturbed by hip pain after surgery. Actigraphy indicated significant reductions in time in bed and activity during sleep, more efficient sleep and less fragmented (restless) sleep. Differences between patients aged < 65 and > or = 65 years were observed. These findings support the hypothesis that relief from the pain of osteoarthritis as a result of THA improves sleep quality. Improvements in sleep contribute to the improved quality of life and day-to-day functioning seen after THA., (Copyright 2003 Elsevier Inc. All rights reserved.)

A nationwide survey (70% response) documented anaesthetists' hours of work, their perceptions about safety limits and their recollection of fatigue-related errors in clinical practice. In the preceding six months, 71% of trainees and 58% of specialists had exceeded their self-defined safety limits for continuous anaesthesia administration. For 50% of trainees and 27% of specialists, their average working week exceeded their own limits for maintaining patient safety, and for 63% of trainees and 40% of specialists, it exceeded their limits for maintaining their personal well-being. Fatigue-related errors were reported by 86% of respondents, with 32% recalling errors in the preceding six months. Specialists were more likely to report a fatigue-related error if they had exceeded their own safety limits for continuous anaesthesia administration, or for weekly work hours. Current measures are not preventing anaesthetists from working hours that they consider to be unsafe for patients or harmful to their own well-being.

We monitored 34 B-727 crewmembers before, during, and after 8-d commercial overnight cargo trips crossing no more than one time zone per 24 h. Daytime sleep episodes were 41% shorter and were rated as poorer than nighttime sleep episodes. When the layover was long enough, crewmembers usually slept again in the evening before going back on night duty. Nevertheless, the total sleep per 24 h on duty days averaged 1.2 h less than pretrip. The circadian temperature rhythm did not adapt completely to night duty, delaying by about 3 h. Self-rated fatigue was highest around the time of the temperature minimum, which occurred near the end of the nighttime duty period. On trip days, crewmembers ate more snacks and there was a marked increase in reports of headaches, congested noses, and burning eyes. Comparisons with daytime short-haul operations confirm that a daytime rest period does not represent the same sleep opportunity as a nighttime rest period of the same duration. We examine regulatory and scheduling options, and personal countermeasure strategies, that could help to reduce sleep loss during overnight cargo operations.

Sleep, circadian rhythms, subjective fatigue, mood, nutrition, and physical symptoms were monitored in flight crews before, during, and after scheduled commercial operations. Duty-related changes in these measures were examined in four different types of air transport: short-haul fixed-wing; short-haul helicopter; domestic overnight cargo; and long-haul. The extent of these changes, and the duty-related and physiological factors contributing to them, are compared among the different operations. During all operations, the level of sleep loss was such that the majority of crewmembers would be expected to have become increasingly sleepy across trip days, with some experiencing performance decrements. In addition, during overnight cargo and long-haul operations, crewmembers were sometimes flying aircraft during the circadian low point in alertness and performance. Specific recommendations for reducing flight crew fatigue are offered for each operating environment.