Fatigue risk management based on self-reported fatigue: Expanding a biomathematical model of fatigue-related performance deficits to also predict subjective sleepiness

Biomathematical models of fatigue can be used to predict neurobehavioral deficits during sleep/wake or work/rest schedules. Current models make predictions for objective performance deficits and/or subjective sleepiness, but known differences in the temporal dynamics of objective versus subjective outcomes have not been addressed. We expanded a biomathematical model of fatigue previously developed to predict objective performance deficits as measured on the Psychomotor Vigilance Test (PVT) to also predict subjective sleepiness as self-reported on the Karolinska Sleepiness Scale (KSS). Four model parameters were re-estimated to capture the distinct dynamics of the KSS and account for the scale difference between KSS and PVT. Two separate ensembles of datasets – drawn from laboratory studies of sleep deprivation, sleep restriction, simulated night work, napping, and recovery sleep – were used for calibration and subsequent validation of the model for subjective sleepiness. The expanded model was found to exhibit high prediction accuracy for subjective sleepiness, while retaining high prediction accuracy for objective performance deficits. Application of the validated model to an example scenario based on cargo aviation operations revealed divergence between predictions for objective and subjective outcomes, with subjective sleepiness substantially underestimating accumulating objective impairment, which has important real-world implications. In safety-sensitive operations such as commercial aviation, where self-ratings of sleepiness are used as part of fatigue risk management, the systematic differences in the temporal dynamics of objective versus subjective measures of functional impairment point to a potentially significant risk evaluation sensitivity gap. The expanded biomathematical model of fatigue presented here provides a useful quantitative tool to bridge this previously unrecognized gap.     

Investigating the influence of time pressure on overtaking maneuvers and crash risk

The research conducted on overtaking maneuver for evaluating drivers’ safety showed adverse effects of urgency on driving performance and decision making. Therefore, a driving simulator study was designed to examine driving performance of the drivers and its implication on overtaking and crash probabilities under increasing time pressure conditions. Eighty-eight participants data were analyzed in the current study. Three different time pressure conditions: No Time Pressure (NTP), Low Time Pressure (LTP), and High Time Pressure (HTP) were considered for analyzing driving performance of the drivers while executing overtaking maneuvers. The driving performance was assessed using minimum time-to-line crossing and coefficient of variation in speed to dissect the safety margin adopted by the drivers while overtaking the lead vehicle. Further, minimum time-to-line crossing and coefficient of variation in speed were considered as explanatory variables to investigate their influence on overtaking and crash probabilities. Parametric survival analysis and Generalized Linear Mixed Models (GLMM) were used to assess the driving performance, overtaking and crash probabilities. The parametric survival analysis showed that minimum time-to-line crossing reduced by 36.7% and 63.8% in LTP and HTP driving conditions, respectively. The GLMM results revealed that coefficient of variation in speed increased by 3.437% in HTP (no significant effect in LTP) as compared to NTP driving conditions. Further, the GLMM results showed that overtaking and crash probabilities decreased with increment in minimum time-to-line crossing and coefficient of variation in speed values. Additionally, it was observed that male drivers took risky decisions than female drivers. Nevertheless, the comparative analysis revealed that male drivers were less prone to crashes than female drivers. Overall, it can be inferred that the drivers take risky decisions with increment in time pressure to complete the driving task, even at the expense of their own safety which exposed them to high likelihood of crashes.     

信任博弈范式真的能测量信任吗?

信任博弈范式测量信任的有效性一直存在争议。一方面, 社会偏好与风险偏好可能在范式变动中对投资信任水平产生影响, 降低信任博弈的内部效度。另一方面, 信任博弈与量表信任的相关水平较低, 这可能和态度与行为差异、测量类型差异以及测量范式的不足有关。虽然存在争议, 但总体而言, 信任博弈范式仍然是较为适宜的信任测量手段。未来信任博弈范式可在：验证信任博弈范式变动的科学性; 进一步澄清信任博弈范式与量表信任的低相关问题; 拓展信任博弈范式的测量维度以及提升信任博弈范式的生态效度等方面继续完善。     

The Challenge of Being a Challenger: Social Dominance Orientation Shapes the Impact of “Challenger vs. Leader” Comparisons

The current research investigates when and how comparative advertising effectiveness is shaped by social dominance orientation (SDO), that is, the degree to which one desires to maintain the status quo in social hierarchies. We examine these issues with regard to “challenger vs. leader” comparisons that seek to change the relative standing of competitors in a product category by documenting the superiority of challenger brands over market leaders. Findings demonstrate that the resistance to change characterizing high (vs. low) SDO individuals makes them respond (1) less favorably to “challenger vs. leader” comparisons that seek to alter the existing category hierarchy and (2) more favorably to “leader vs. challenger” comparisons that preserve this status quo in the category hierarchy. The theoretical implications of these findings are discussed, as are avenues for future research.     

Fukushima ETHOS: Post-Disaster Risk Communication,Affect, and Shifting Risks

ETHOS Fukushima is a risk communication (RC) program organized after the Fukushima nuclear accident by the International Commission on Radiological Protection and other international organizations supported by the Japanese government. ETHOS has been hailed as a model RC that is participatory and dialogue-based. Yet the critical and feminist literature has shown the need for analyzing the power relations in participatory projects, and for analyzing affect as a target of management by neoliberal governmentality. The affective work of ETHOS is characterized by narratives of self-responsibility, hope and anticipation, and transnational solidarity with Chernobyl victims. These resonate with the affective regime under neoliberalism that privileges self-responsibility, anticipation, maximization of emotional potential, and cosmopolitan empathy. This particular regime of affect has been integral in shifting risk from the nuclear industry and the government to individual citizens. ETHOS Fukushima has supported continued residence in contaminated areas. It has helped portray the reduction of government/industry responsibility as morally defensible, and the decision to stay in Fukushima as a free choice made by hopeful and determined citizens. At the same time, ETHOS has helped characterize the state’s and the nuclear industry’s roles in cleaning up and compensating the victims as restricting individual freedom and demoralizing the local people. The recent RC literature increasingly argues for a positive assessment of emotion, but this argument warrants careful analysis, as emotion is socially regulated and entangled in power relations. Moreover, deploying affective tropes is a crucial technique of neoliberal governmentality, especially because of affect’s seemingly oppositional and external relationship to neoliberalism.     

Methodological considerations in developing measures of HIV risk-relevant behaviors and attitudes: An empirical illustration

Abstract

This paper describes the pilot testing of a survey designed to assess the prevalence of HIV exposure risk-relevant behaviors and associated attitudes, beliefs and knowledge in a heterogeneous, ethnically diverse, sexually active population (the US Army). The specific objectives for the pilot test were to: (1) define optimal survey question formats for behavioral and attitude items; (2) identify questions that were poorly worded or that would not contribute to the overall objectives of the survey; (3) assess the extent to which respondents could accurately follow instructions; (4) identify appropriate and culturally relevant terminology for sensitive items; (5) determine the appropriate timeframe for recall of simple and complex sexual behaviors; (6) assess the degree of respondent honesty and belief in the anonymity of the survey results.     

Predictors of needle-sharing behavior among IDUs entering treatment

Abstract

Public funded treatment intake data from 3905 injection drug users were analyzed to identify correlates of reported needle sharing. Respondents included all first admissions to treatment from July 1, 1988 to June 30, 1989 in the city and county of San Francisco. More previous experience in drug treatment predicted lower rates of needle sharing (OR = 0.85, 95% C.I.= 0.79 - 0.92). Young age, cocaine use and white or Hispanic ethnicity predicted higher rates of needle sharing. The finding that drug treatment reduces the frequency of needle sharing in this population has important policy implications; these data support the role of treatment availability in reducing the spread of HIV among injection drug users.     

The relation between risk perceptions and physical activity among older adults: A prospective study

Past studies have found that risk perceptions of suffering from diseases play an important role in the development of intentions to perform physical activity (PA). According to the behaviour motivation hypothesis, perceived risk could be positively and directly related to PA, but this possibility has been ignored and/or underestimated. Accounting for recent methodological developments on the importance of study design and risk perception assessment, the purpose of the present study was to examine the risk-perceptions–PA relationship among older adults. Participants (N?=?143) aged from 61 to 70 years initially underwent measurement of risk perceptions, baseline PA, socio-demographic and health factors. Six months later, they were asked about their PA participation. Multiple regression analyses revealed that perceived risk of suffering from diseases and conditions without regular PA participation was an independent positive predictor of later PA, over and beyond baseline behaviour, socio-demographic and health variables. This study fills a gap in the existing literature on the PAs of older adults and reveals that risk perceptions are directly linked to their participation. In addition, it extends existing knowledge in health psychology on the behaviour motivation hypothesis, and emphasises the necessity of methodological adjustments when assessing the risk-perception–behaviour relationship.     

Selective review,optimism and HIV risk perception

Abstract

Research suggests that review of risk factors increases optimism about health. The present experimental study explored the effects of reviewing risk increasing and risk decreasing factors on HIV risk perception (own risk, others' risk, optimism), self efficacy and behavioural intentions. 164 heterosexual subjects completed a questionnaire concerning their beliefs about HTV and their sexual behaviour. Subjects were allocated to either the risk increasing condition (eg. since being sexually active how often have you asked your partners HIV status?), the risk decreasing condition (eg. since being sexually active how often have you tried to select your sexual partners carefully?), or a control group. The results suggest that review of risk decreasing factors increased optimism and that this change in optimism was related to an increase in perceived others' risk. The results are discussed in terms of theories of selective focus and egocentricism in risk perception and the implications for health promotion.