Validity of Telemetric-Derived Measures of Heart Rate Variability: A Systematic Review

Heart rate variability (HRV) is a widely accepted indirect measure of autonomic function with widespread application across many settings. Although traditionally measured from the ‘gold standard’ criterion electrocardiography (ECG), the development of wireless telemetric heart rate monitors (HRMs) extends the scope of the HRV measurement. However, the validity of telemetric-derived data against the criterion ECG data is unclear. Thus, the purpose of this study was twofold: (a) to systematically review the validity of telemetric HRM devices to detect inter-beat intervals and aberrant beats; and (b) to determine the accuracy of HRV parameters computed from HRM-derived inter-beat interval time series data against criterion ECG-derived data in healthy adults aged 19 to 62 yrs. A systematic review of research evidence was conducted. Four electronic databases were accessed to obtain relevant articles (PubMed, EMBASE, MEDLINE and SPORTDiscus. Articles published in English between 1996 and 2016 were eligible for inclusion. Outcome measures included temporal and power spectral indices (Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology (1996). The review confirmed that modern HRMs (Polar® V800™ and Polar® RS800CX™) accurately detected inter-beat interval time-series data. The HRV parameters computed from the HRM-derived time series data were interchangeable with the ECG-derived data. The accuracy of the automatic in-built manufacturer error detection and the HRV algorithms were not established. Notwithstanding acknowledged limitations (a single reviewer, language bias, and the restricted selection of HRV parameters), we conclude that the modern Polar® HRMs offer a valid useful alternative to the ECG for the acquisition of inter-beat interval time series data, and the HRV parameters computed from Polar® HRM-derived inter-beat interval time series data accurately reflect ECG-derived HRV metrics, when inter-beat interval data are processed and analyzed using identical protocols, validated algorithms and software, particularly under controlled and stable conditions

Quantification of movement characteristics in women’s English Premier elite domestic rugby union

This study aims were to determine the positional physical requirements of English domestic women’s rugby union match-play. Global positioning system data (Catapult Minimax S4) were collected at 10 Hz of 129 competitive player games from the Tyrrells Premier15 league. Players were classified according to broad (Forwards, Backs) and specific positions (front-, second-, back-row, scrum-half, inside-, and outside-backs). Total distances, maximum speed, and player loads were calculated. Mean total distance was 4982 m and was similar between the Forwards and Backs, with second-row players covering the most (5297 m) and outside-backs the least (4701 m). Inside- and outside-backs covered a significantly greater distance at high speed running (134 m; 178 m) and sprinting (74 m; 92 m) speeds, respectively, whereas the second- and back-row covered greater distances jogging (1966 m; 1976 m) and the front-row spent the greatest overall distance walking (2613 m). Outside-backs reached greater maximum speed than all other positions (24.9 km.h-1). The mean player load was highest in the back-row (562 AU) and second-row (555 AU) and these were higher than the outside-backs (476 AU). These findings indicate that the demands placed on female rugby players are position specific and differ from male players. Additionally, the data are the first obtained from the 10 Hz GPS and from within English domestic women’s rugby, thus adding to the overall limited data available on women’s rugby union

Predictors of vitamin D status and its association with parathyroid hormone in young New Zealand children.

BACKGROUND: Despite increased awareness of the adverse health effects of low vitamin D status, few studies have evaluated 25-hydroxyvitamin D [25(OH)D] status in young children. OBJECTIVES: We aimed to assess vitamin D status on the basis of 25(OH)D and its relation with parathyroid hormone (PTH) and to identify possible predictors of 25(OH)D status in young children living in a country with minimal vitamin D fortification. DESIGN: Serum 25(OH)D and PTH concentrations were measured in a cross-sectional sample of children aged 12-22 mo [n = 193 for 25(OH)D, n = 144 for PTH] living in Dunedin, New Zealand (latitude: 45 degrees S). Anthropometric, dietary, and sociodemographic data were collected. RESULTS: The majority of children sampled in the summer (94%; 47 of 50) had 25(OH)D >50 nmol/L; however, nearly 80% of children sampled in the winter (43 of 55) had serum concentrations 60-65 nmol/L, a plateau in PTH was evident. CONCLUSIONS: Seasonal variation in 25(OH)D concentration implies that postsummer vitamin D stores were insufficient to maintain status >50 nmol/L year-round. Examination of the predictors of 25(OH)D in our model shows few modifiable risk factors, and thus effective dietary strategies may be required if future research determines that children with 25(OH)D concentrations <50 nmol/L are at significant health risk. This trial was registered at www.actr.org.au as ACTRN12605000487617

From ‘rock stars’ to ‘hygiene factors’:teachers at private accountancy tuition providers

In this paper, we examine the role, status and autonomy of teachers at English private accountancy tuition providers from 1980 to the present. We argue that, during this period, teachers transformed from ‘rock stars’ who enjoyed significant status and autonomy over their work to ‘hygiene factors’ in a largely standardised and commodified teaching environment. Growing cost pressures on tuition providers and an increasing emphasis on the quality and consistency of the learning experience are identified as significant factors in this transformation. We discuss these findings with reference to current developments towards corporatisation and marketisation in the English higher education sector

Surveillance of compliance with tobacco regulations in Örebro County, Sweden: a mixed methods study after the ban of test purchases

<p>Abstract</p> <p>Background</p> <p>Tobacco has long been known to be one of the most common reasons for sickness and premature deaths in the world. An important aspect of tobacco use is the youth's access to tobacco, and surveillance visits are one way to make sure how retailers are complying with age limit in the tobacco law. In Örebro County, Sweden, a project to reinforce the tobacco legislation was carried out in 2009-2010. One part of the project was surveillance visits that were done according to three different themes, called thematic surveillance.</p> <p>Methods</p> <p>This study is an evaluation of the results from thematic surveillance and has a mixed methods approach. The quantitative analyses concerns protocols from 217 surveillance visits, where questions were asked about three themes (self-monitoring programs; marketing; labeling of products and pricing). In addition, questionnaires filled out by six tobacco administrators who worked within the project were analyzed qualitatively by content analysis in order to study their perceptions and opinions of the project.</p> <p>Results</p> <p>This study shows that half of the visited retailers had self-monitoring programs. Lack of self-monitoring programs was significantly more common in smaller stores/kiosks and at restaurants. Further, the tobacco administrators who worked within the project perceived thematic surveillance as a good method for accomplishing better structure in surveillance work, but not as effective as purchase attempts (mystery shopping).</p> <p>Conclusions</p> <p>Thematic surveillance was perceived as positive and the method was also regarded to be a good way to work with surveillance. However, the method could be developed further for optimal use and better effect at the retailers. It is clear that people who work with tobacco prevention at the local level in Örebro County want to use purchase attempts as a surveillance method, and that they believe that purchase attempts is the best way to make sure if store comply with the tobacco law.</p

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Exploring practices and perceptions of alcohol use during pregnancy in England and Sweden through a cross-cultural lens.

Background: Qualitative studies have aimed to understand why some women continue to drink during pregnancy; however, there is a lack of comparative cross-cultural research. We aimed to explore perceptions and practices of alcohol use during pregnancy in England and Sweden. Methods: Semi-structured interviews were conducted with 21 parents in Merseyside, England and 22 parents in Örebro County, Sweden. Interviews were audio recorded, transcribed verbatim and translated. Data were analyzed using thematic analysis. Results: The majority of women in both countries abstained from alcohol when they found out they were pregnant, despite alcohol being part of many social contexts before pregnancy. Nine of the seventeen English women drank at some point during pregnancy, typically on special occasions. Most parents felt women should modify their alcohol intake when they become mothers, though several English parents argued that responsible motherhood did not necessarily equate to abstinence. Swedish parents held strong opinions against drinking during pregnancy and argued that any amount of alcohol could harm the foetus. English parents' opinions were divided; some were skeptical of whether low to moderate drinking was associated with risks. Conclusions: Practices and attitudes towards alcohol use during pregnancy and views on foetal rights and responsibilities of pregnant women differed in England and Sweden. Shared social norms around drinking may be shaped within the policy context of pregnancy drinking guidelines, determining whether women consume alcohol or not