Dynamical analysis of winter terrain park jumps

Jump features in winter terrain parks frequently pose a hazard to patrons and may represent a significant liability risk to winter resorts. By performing a simple dynamic analysis of terrain park jumps, the relative risk to impact injuries for any proposed jump design can be quantified thereby allowing terrain park designers to minimize the risk from this class of injury.     

Tracking club sport participation from childhood to early adulthood

This study examined the strength of tracking sport participation from childhood to early adulthood among the Dunedin Multidisciplinary Health and Development Study cohort. Participation in sport, dance, or gymnastics as part of a club or group (outside of school) was assessed at ages 7, 9, 15, 18, and 21 years. In addition to the traditionally used correlation coefficients, summary statistics (intraclass correlations; ICC) from random effect models and stability coefficients from generalized estimating equations (GEE) were calculated using all the longitudinal data and controlling for the influence of covariates on tracking strength. Correlation coefficients revealed statistically significant tracking of club sport participation (7-21 years) at low levels (r = .07-0.28). The ICC summary statistic (0.23) was consistent with this, while the GEE suggested moderate tracking (0.59). The results of this study suggest that encouraging sport participation during childhood and adolescence may result in a modest increase in the likelihood of participation later in life. However, the substantial movement into and out of sport participation observed here and in other studies cautions against relying solely on sport promotion among youth as a strategy to promote lifelong participation.     

An objective method for depicting team performance in elite professional rugby union

Using a two-study approach, we examined a methodology for objectively depicting team performance and form in a professional rugby union side. Study 1 developed standardized indicators to examine a team's performance in a single match relative to their previous matches over a domestic season via a performance report and form chart. This resulted in standardized performance indicators that provided instant and coherent feedback on the team's performance relative to previous standards. Study 2 then utilized this methodology to compare a match between two professional sides, played the following season, to assess the extent to which the performance by one team affected that of the other. Comparison of the two teams' performances, for the match they played against each other, identified a drop in relative performance (against previous standards) for both teams on the same performance indicators. This appeared to be due to the match being a close, hard-fought contest particularly in the tackle and around the gain-line. The findings of the two studies suggest an accurate and viable methodology for depicting team performance that is superior to the global measures previously adopted. Presenting teams' current standardized performances (i.e. form) on a single visual scale also has utility for coaches within an applied setting. Future research should further investigate the effect of one team's performance on another through both individual and team outcomes.     

Factor structure of the Wechsler Intelligence Scale for Children-Revised,Peabody Picture Vocabulary Test,and Peabody Individual Achievement Test in a psychiatric sample

This study analyzed the factor structure of the Wechsler Intelligence Scale for Children-Revised (WISC-R), the Peabody Picture Vocabulary Test (PPVT), and the Peabody Individual Achievement Test (PIAT) in a psychiatric sample that ranged in age from 6 to 16 years (mean age = 11.1 years; SD = 3.0). The resultant factor structure of this sample was compared with patterns reported on normal and learning-disabled children. The subjects were 329 children under inpatient and outpatient care who had been referred for emotional disturbances. The results were similar to previous factor analytic studies of the WISC-R and PIAT, showing four factors: Verbal Comprehension, Verbal Achievement, Perceptual Organization, and Number Facility. The implications for the interpretation of these tests in a psychiatric sample and the appropriateness of a maximum likelihood technique in analysis of psychometric data are discussed.