Validity of the Global Physical Activity Questionnaire (GPAQ) in assessing levels and change in moderate-vigorous physical activity and sedentary behaviour

Background

Feasible, cost-effective instruments are required for the surveillance of moderate-to-vigorous physical activity (MVPA) and sedentary behaviour (SB) and to assess the effects of interventions. However, the evidence base for the validity and reliability of the World Health Organisation-endorsed Global Physical Activity Questionnaire (GPAQ) is limited. We aimed to assess the validity of the GPAQ, compared to accelerometer data in measuring and assessing change in MVPA and SB.

Participants (n = 101) were selected randomly from an on-going research study, stratified by level of physical activity (low, moderate or highly active, based on the GPAQ) and sex. Participants wore an accelerometer (Actigraph GT3X) for seven days and completed a GPAQ on Day 7. This protocol was repeated for a random sub-sample at a second time point, 3–6 months later. Analysis involved Wilcoxon-signed rank tests for differences in measures, Bland-Altman analysis for the agreement between measures for median MVPA and SB mins/day, and Spearman’s rho coefficient for criterion validity and extent of change.

95 participants completed baseline measurements (44 females, 51 males; mean age 44 years, (SD 14); measurements of change were calculated for 41 (21 females, 20 males; mean age 46 years, (SD 14). There was moderate agreement between GPAQ and accelerometer for MVPA mins/day (r = 0.48) and poor agreement for SB (r = 0.19). The absolute mean difference (self-report minus accelerometer) for MVPA was −0.8 mins/day and 348.7 mins/day for SB; and negative bias was found to exist, with those people who were more physically active over-reporting their level of MVPA: those who were more sedentary were less likely to under-report their level of SB. Results for agreement in change over time showed moderate correlation (r = 0.52, p = 0.12) for MVPA and poor correlation for SB (r = −0.024, p = 0.916).

Levels of agreement with objective measurements indicate the GPAQ is a valid measure of MVPA and change in MVPA but is a less valid measure of current levels and change in SB. Thus, GPAQ appears to be an appropriate measure for assessing the effectiveness of interventions to promote MVPA.

Urban and rural differences in risk of admission to a care home: a census-based follow-up study

Research on admissions to care homes for older people has paid more attention to individual and social characteristics than to geographical factors. This paper considers rural-urban differences in household composition and admission rates. Cohort: 51,619 people aged 65 years or older at the time of the 2001 Census and not living in a care home, drawn from a data linkage study based on c.28% of the Northern Ireland population.Living alone was less common in rural areas; 25% of older people in rural areas lived with children compared to 18% in urban areas. Care home admission was more common in urban (4.7%) and intermediate (4.3%) areas than in rural areas (3.2%). Even after adjusting for age, sex, health and living arrangements, the rate of care home admission in rural areas was still only 75% of that in urban areas.People in rural areas experience better family support by living as part of two or three generation households. Even after accounting for this difference, older rural dwellers are less likely to enter care homes; suggesting that neighbours and relatives in rural areas provide more informal care; or that there may be differential deployment of formal home care services.

Restorative Justice and Sex Offending

This essay examines the origins and uses of restorative justice with sexual offending and the contemporary challenges and controversies surrounding this. It charts the range of ad hoc initiatives which have sought to apply a restorative form of intervention with violent or sexual offending from first time and ‘acquaintance’ rape as well as young sexual abusers to high risk sexual offenders in the form of circles of support and accountability. Such schemes are often presented as a counter to the failings of retributive forms of justice and are premised on Braithwaite’s (1989) notion of ‘reintegrative shaming’ that seek to reintegrate offenders into the community. Critics of restorative justice traditionally put forward a number of core objectives when restorative justice is applied to serious forms of offending such as sexual offending. The essay also sets out and seeks to counter these principal challenges and how they may be overcome. For the most part, however, restorative justice has failed to reach its potential as a fully fledged sentencing rationale in being applied as a mainstream response to a wide range of offending including that at the higher end of the spectrum. The essay also seeks to examine barriers to restorative justice within contemporary penal policy and to highlight some of the most controversial applications of the restorative paradigm including those related to clergy sexual abuse. It concludes by offering some thoughts on the future of restorative justice as a mainstream responses to serious forms of offending.

Preschool Children's Awareness of and Attitudes Toward Difference: A Study of 3- and 4-Year-Old Children in Northern Ireland

This paper presents the findings of a large-scale survey (n = 1,049) of the ethnic awareness and attitudes of 3-4 year old children in Northern Ireland. In drawing upon and applying Bourdieu’s notion of habitus, the paper demonstrates how even at this age, the children are already beginning to embody and internalize the cultural habits and dispositions of their respective ethnic groups. This was found in relation to the children’s: friendships choices; preferences for particular national flags; and dispositions towards specific sports associated with their respective communities. Informed by the work of Bourdieu, the paper concludes by arguing for the need for greater use of quantitative methods employing multivariate and multilevel statistical analyses and for these to be based on a more open and meaningful engagement with the findings of indepth qualitative and ethnographic research in this area.

Aesthetic Perceptions - Is There a Difference?

Introduction: In recent times, the demand for aesthetic dentistry has increased, with patients presenting for treatment expecting an improvement in their aesthetics. Therefore, it is increasingly important for the dental profession to appreciate perceptions of dental aesthetics in order to provide a patient-centred service.

Objectives: The aim of this study is to quantify perceptions of aesthetics using a cross-sectional survey design. The hypotheses being tested were that differences exist in aesthetic perceptions of 1) dentists and dental students, 2) different age ranges and 3) gender.

Methods: A questionnaire was distributed to dental staff and students in the Cork University Dental School and Hospital. The questionnaire sought information relating to aesthetic perceptions by asking participants to compare photographs of smiles.

Results: 100 questionnaires were returned. It was found that differences existed in perceptions of dentists and dental students when certain aspects of a smile were evaluated, in particular when a minor flaw was present in a smile in addition to the major flaw being tested. Assuming that flaws were detected, more dental students (34%) than dentists (26%) were found to prioritise colour above more subtle flaws, such as a centreline shift. However, most results between the two groups are comparable in terms of their prioritising of importance of particular aspects of a smile, with no large significant differences.

Conclusion: Differences exist in aesthetic perceptions of dentists and dental students, especially with regard to tooth colour.

Machine learning for transient discovery in Pan-STARRS1 difference imaging

Efficient identification and follow-up of astronomical transients is hindered by the need for humans to manually select promising candidates from data streams that contain many false positives. These artefacts arise in the difference images that are produced by most major ground-based time-domain surveys with large format CCD cameras. This dependence on humans to reject bogus detections is unsustainable for next generation all-sky surveys and significant effort is now being invested to solve the problem computationally. In this paper, we explore a simple machine learning approach to real-bogus classification by constructing a training set from the image data of similar to 32 000 real astrophysical transients and bogus detections from the Pan-STARRS1 Medium Deep Survey. We derive our feature representation from the pixel intensity values of a 20 x 20 pixel stamp around the centre of the candidates. This differs from previous work in that it works directly on the pixels rather than catalogued domain knowledge for feature design or selection. Three machine learning algorithms are trained (artificial neural networks, support vector machines and random forests) and their performances are tested on a held-out subset of 25 per cent of the training data. We find the best results from the random forest classifier and demonstrate that by accepting a false positive rate of 1 per cent, the classifier initially suggests a missed detection rate of around 10 per cent. However, we also find that a combination of bright star variability, nuclear transients and uncertainty in human labelling means that our best estimate of the missed detection rate is approximately 6 per cent.

Conical Horn Antenna with Spiral Phase Plate for Difference Pattern Generation

This paper describes the performance characteristics and experimental validation of a compact conical horn antenna with a dielectric cylinder spiral phase plate attached at its aperture. This performs the function of a spatial phase imprinting device creating a helical wave-front which results in a null in the far field radiation pattern of the antenna assembly.