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1.
Corey Jones Emily Graybill Brian Barger Andrew T. Roach 《Psychology in the schools》2020,57(6):923-936
Through this study we compared different informants and different behavior screening tools that are available to screen for behavioral and emotional risk. We examined screening results from 100 students from a high school with a high achiever's magnet program in the Southeastern United States (school demographics: 71% female and 79% black, non-Hispanic). This school conducted behavior screening using both teacher-report via the Student Risk Screening Scale, Internalizing/Externalizing (SRSS-IE) and student report via the Strengths and Difficulties Questionnaire (SDQ). Nonparametric correlation tests were conducted between the SRSS-IE and SDQ externalizing and internalizing scores. Generalized linear regression models were created based on the data (demographics, internalizing, and externalizing scores on both screening tools) to model the two count outcomes (office discipline referrals [ODRs] and absences). Diagnostic accuracy metrics were generated from the scores on both the SRSS-IE and SDQ with the outcome measures (ODRs and absences). Externalizing scores on both screening tools had statistically significant low correlations. The ODR model contained two predictors: externalizing score on the SRSS-IE and internalizing score on the SDQ, while the absence model contained grade and the externalizing score on the SDQ. The highest accuracy and agreement values were seen between students with elevated risks on both screening measures and ODRs. The results confirmed that teacher and student reporting, as well as different screening tools, will result in some different students being identified. The choice of informant and screening tools should be dependent on the needs and resources of the school. 相似文献
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Benjamin K. Williams Ross H. Sanders Joong Hyun Ryu Philip Graham-Smith Peter J. Sinclair 《Journal of sports sciences》2020,38(10):1115-1123
ABSTRACT To maintain the accuracy of squash shots under varying conditions, such as the oncoming ball’s velocity and trajectory, players must adjust their technique. Although differences in technique between skilled and less-skilled players have been studied, it is not yet understood how players vary their technique in a functional manner to maintain accuracy under varying conditions. This study compared 3-dimensional joint and racket kinematics and their variability between accurate and inaccurate squash forehand drives of 9 highly skilled and 9 less-skilled male athletes. During inaccurate shots, less-skilled players hit the ball with a more open racket, demonstrating a difference in this task-relevant parameter. No joint kinematic differences were found for accuracy for either group. Coordinated joint rotations at the elbow and wrist both displayed a “zeroing-in” effect, whereby movement variability was reduced from the initiation of propulsive joint rotation to a higher consistency at ball-impact; potentially highlighting the “functionality” of the variability prior to the impact that enabled consistent task-relevant parameters (racket orientation and velocity) under varying conditions. Further, highly skilled players demonstrated greater consistency of task-relevant parameters at impact than less-skilled players. These findings highlight the superior ability of highly skilled players to adjust their technique to achieve consistent task-relevant parameters and a successful shot. 相似文献
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Benjamin Kane Williams Ross H. Sanders Joong Hyun Ryu Pitre C. Bourdon Philip Graham-Smith Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):202-214
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics. 相似文献
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Purpose: Overuse injuries are common in sport, but complete understanding of injury risk factors remains incomplete. Although biomechanical studies frequently examine musculoskeletal injury mechanisms, human movement variability studies aim to better understand neuromotor functioning, with proposed connections between overuse injury mechanisms and changes in motor variability. Method: In a narrative review, we discuss the variability-overuse injury hypothesis, which suggests repeated load application leads to mechanical tissue breakdown and subsequent injury when exceeding the rate of physiological adaptation. Due to the multidisciplinary nature of this hypothesis, we incorporate concepts from motor control, neurophysiology, biomechanics, as well as research design and data analysis. We therefore summarize multiple perspectives while proposing theoretical relationships between movement variability and lower extremity overuse injuries. Results: Experimental data are presented and summarized from published experiments examining interactions between experimental task demands and movement variability in the context of drop landing movements, along with comparisons to previous movement variability studies. Conclusion: We provide a conceptual framework for sports medicine researchers interested in predicting and preventing sports injuries. Under performance conditions with greater task demands, we predict reduced trial-to-trial movement variability that could increase the likelihood of overuse injuries. 相似文献
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