Direct Estimation Evaluation of Rehabilitation Patients by Non-Expert Judges

The investigation completed by Lipp (Evaluation of rehabilitation patients by direct estimation procedures, Ph.D. Dissertation, University of North Dakota, 1969) demonstrated that exceedingly reliable ratio scale measurement of degree of physical disability could be achieved by expert judges (Js) using direct estimation procedures. In the present investigation, 10 J^s without formal rehabilitation training or experience made magnitude estimations of degree of physical disability shown by 10 rehabilitation patients in the modalities of ambulation and transfer. The patients\u27 behaviors were depicted by the videotape recording which were used in the Lipp investigation. The magnitude estimation portion of the Lipp investigation was replicated except for the use of non-expert Js. The Js also made similarity estimations for the 45 pairs of patient-stimuli in the transfer modality. Interjudge reliability for the magnitude estimation scales was highly significant (p\u3c.001). Product-moment correlations between the magnitude estimation scales of non-experts and experts demonstrated extremely close correspondence (r = .999, r = .998). Judgmental variability was shown to increase with subjective magnitude as predicted by Ekman\u27s law. A ratio scale was derived from the similarity estimations which corresponded closely to the magnitude estimation scales of experts and non-experts (r = .97). Cluster analyses of coefficients of similarity derived from the magnitude estimation scales and of the obtained similarity estimations resulted in clusters of patient-stimuli which were psychologically meaningful and which corresponded almost exactly to the clusters which Lipp obtained. The discussion examined the usefulness of non-expert Js, the validity of their judgment, and the relationship of their judgment to that of experts

Morning quiet-time ionospheric current reversal at mid to high latitudes

The records of an array of magnetometers set up across the Australian mainland are examined. In addition to a well-defined current whorl corresponding to the ionospheric <i>S<sub>q</sub></i> current system, another system of eastward flowing currents is often found in the early morning. The system is most easily identified at observatories poleward of the focus of the <i>S<sub>q</sub></i> system, where a morning reversal from eastward to westward currents can be seen. The time of the reversal is usually later, sometimes up to 12h local noon, in June (Southern Winter) than in other seasons. There is some evidence of a similar current system at other longitudes and in the Northern Hemisphere. An important outcome of the study is that it enables identification of which features of a daily variation of the northward magnetic field Δ<i>X</i> relate to an <i>S<sub>q</sub></i> current whorl and which must be attributed to some other current system

Magnetohydrodynamic activity inside a sphere

We present a computational method to solve the magnetohydrodynamic equations in spherical geometry. The technique is fully nonlinear and wholly spectral, and uses an expansion basis that is adapted to the geometry: Chandrasekhar-Kendall vector eigenfunctions of the curl. The resulting lower spatial resolution is somewhat offset by being able to build all the boundary conditions into each of the orthogonal expansion functions and by the disappearance of any difficulties caused by singularities at the center of the sphere. The results reported here are for mechanically and magnetically isolated spheres, although different boundary conditions could be studied by adapting the same method. The intent is to be able to study the nonlinear dynamical evolution of those aspects that are peculiar to the spherical geometry at only moderate Reynolds numbers. The code is parallelized, and will preserve to high accuracy the ideal magnetohydrodynamic (MHD) invariants of the system (global energy, magnetic helicity, cross helicity). Examples of results for selective decay and mechanically-driven dynamo simulations are discussed. In the dynamo cases, spontaneous flips of the dipole orientation are observed.Comment: 15 pages, 19 figures. Improved figures, in press in Physics of Fluid

Risky youth to risky adults: Sustained increased risk of crash in the DRIVE study 13 years on.

The objective of this study was to investigate if drivers who exhibit risky driving behaviours during youth (aged 17-24 years) have an increased risk of car crash up to 13 years later. We used data from the DRIVE study, a 2003/04 survey of 20,806 young novice drivers in New South Wales, Australia. The data were linked with police crash, hospital and deaths data up to 2016. We analysed differences in crash associated with 13 items of risky driving behaviours using negative binominal regression models adjusted for driver demographics, driving exposure and known crash risk factors. The items were summarised in one index and grouped into quintiles for the analysis. After adjusting for confounding, drivers of the third (RR 1.16, 95% CI 1.05-1.30), fourth (RR1.22, 95% CI1.09-1.36) and fifth quintile (RR 1.36, 95% CI 1.21-1.53) had higher crash rates compared to the lowest risk-takers. Drivers with the highest scores on the risky driving measure had higher rates of crash related hospital admission or death (RR 1.92, 95% CI 1.13-3.27), crashes in wet conditions (RR 1.35,95% CI 1.05-1.73), crashes in darkness (RR 1.55, 95% CI 1.25-1.93) and head-on crashes (RR 2.14, 95% CI 1.07-4.28), compared with drivers with the lowest scores. Novice adolescent drivers who reported high levels of risky driving when they first obtained a driver licence remained at increased risk of crash well into adulthood. Measures that successfully reduce early risky driving, have the potential to substantially reduce road crashes and transport related injuries and deaths over the lifespan

Participant preferences for an aboriginal-specific fall prevention program: Measuring the value of culturally-appropriate care

© 2018 Angell et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background Culturally-specific services are central to efforts to improve the health of Aboriginal Australians. Few empirical studies have demonstrated the value of such services relative to mainstream alternatives. Objective To assess the preferences and willingness to pay (WTP) of participants for attending a class and the relative importance of transport, cost and cultural-appropriateness in the choices made by participants. Design A discrete choice experiment (DCE) was conducted alongside a study of a culturally-specific fall-prevention service. Attributes that were assessed were out-of-pocket costs, whether transport was provided and whether the class was Aboriginal-specific. Choices of participants were modelled using panel-mixed logit methods. Results 60 patients completed the DCE. Attending a service was strongly preferred over no service (selected 99% of the time). Assuming equivalent efficacy of fall-prevention programs, participants indicated a preference for services that were culturally-specific (OR 1.25 95% CI: 1.00–1.55) and incurred lower out-of-pocket participant costs (OR 1.19 95% CI 1.11–1.27). The provision of transport did not have a statistically significant influence on service choice (p = 0.57). Discussion and conclusions This represents the first published DCE in the health field examining preferences amongst an Aboriginal population. The results empirically demonstrate the value of the culturally-specific element of a program has to this cohort and the potential that stated-preference methods can have in incorporating the preferences of Aboriginal Australians and valuing cultural components of health services. Note on terminology As the majority of the NSW Aboriginal and Torres Strait Islander population is Aboriginal (97.2%), this population will be referred to as ‘Aboriginal’ in this manuscript

Are there sex differences in crash and crash-related injury between men and women? A 13-year cohort study of young drivers in Australia

BackgroundYoung men have long been known to be disproportionately impacted by road crash and crash-related injury compared to young women and older drivers. However, there is limited insight into how sex differences in crash and crash-related injury changes over time as men and women get older and gain more driving experience. To explore sex differences in crash and crash-related injury, we undertook a sex disaggregated analysis in a large longitudinal cohort of over 20,000 young drivers in New South Wales, Australia, for up to 13 years after they first attained their independent car driver licence.MethodsDRIVE Study survey data from 2003-04 were linked with police, hospital and deaths data up to 2016. Sex differences were analysed using cumulative incidence curves investigating time to first crash and in negative binominal regression models adjusted for driver demographics and crash risk factors.ResultsAfter adjusting for demographics and driving exposure, compared with women, men had 1.25 (95% CI 1.18-1.33), 2.07 (1.75-2.45), 1.28 (95% CI 1.13-1.46), 1.32 (95% CI 1.17-1.50) and 1.59 (95% CI 1.43-1.78) times higher rates of any crash, single vehicle crash, crash on streets with a speed limit of 80 km/h or above, crash in wet conditions and crash in the dark, respectively. By contrast, men were less likely to be involved in crashes that resulted in hospitalisation compared to women 0.73 (95% CI 0.55-0.96).ConclusionsYoung men are at increased risk of crash, and this risk persists as they get older and gain more driving experience. Despite lower risk of crash, women are at higher risk of crash related injury requiring hospitalisation. These differences in men's and women's risk of crash and injury signal the need for better understanding of how sex and/or gender may contribute to risk of crash and injury across the life-course

Evidence Synthesis for Complex Interventions Using Meta-Regression Models

This study was funded by the Canadian Institutes of Health Research (grants FDN-143269 and FRN-123345) and a research fellowship held by K.J.K. (Frederick Banting and Charles Best Canada Graduate Scholarship GSD-134936). N.M.I. holds a Canada Research Chair (Tier 2) in Implementation of Evidence Based Practice and a Clinician Scientist Award from the Department of Family and Community Medicine at the University of Toronto (Toronto, Ontario, Canada). J.M.G. held a Canada Research Chair in Health Knowledge Transfer and Uptake during the time of the study’s conduct and was supported by a Foundation Grant from the Canadian Institutes of Health Research. D.M. was supported by a University of Ottawa Research Chair during the time of study conduct.Peer reviewedPublisher PD