45 research outputs found
Inter-rater reliability and validity of the Australian Football League\u27s kicking and handball tests
Talent identification tests used at the Australian Football League’s National Draft Combine assess the capacities of athletes to compete at a professional level. Tests created for the National Draft Combine are also commonly used for talent identification and athlete development in development pathways. The skills tests created by the Australian Football League required players to either handball (striking the ball with the hand) or kick to a series of 6 randomly generated targets. Assessors subjectively rate each skill execution giving a 0-5 score for each disposal. This study aimed to investigate the inter-rater reliability and validity of the skills tests at an adolescent sub-elite level. Male Australian footballers were recruited from sub-elite adolescent teams (n=121, age=15.7 ± 0.3 years, height=1.77 ± 0.07 m, mass=69.17 ± 8.08 kg). The coaches (n=7) of each team were also recruited. Inter-rater reliability was assessed using Inter-class correlations (ICC) and Limits of Agreement analysis. Both the kicking (ICC=0.96, P\u3c0.01) and handball tests (ICC=0.89, P\u3c0.01) demonstrated strong reliability and acceptable levels of absolute agreement. Content validity was determined by examining test scores sensitivity to laterality and distance. Concurrent validity was assessed by comparing coaches’ perceptions of skill to actual test outcomes. Multivariate analysis of variance (MANOVA) examined the main effect of laterality, with scores on the dominant hand (P=0.04) and foot (P\u3c0.01) significantly higher compared to the non-dominant side. Follow-up univariate analysis showing significant differences at every distance in the kicking test. A poor correlation was found between coaches’ perceptions of skill and testing outcomes. The results of this study demonstrate both skill tests demonstrate acceptable inter-rater reliable. Partial content validity was confirmed for the kicking test, however further research is required to confirm validity of the handball test
The validity and reliability of the Basketball Jump Shooting Accuracy Test
The aim of this study was to examine the content validity, construct validity and reliability of the newly developed Basketball Jump Shooting Accuracy Test (BJSAT). Basketball athletes from different playing levels (State Basketball League [SBL], n = 30, age: 22.7 ± 6.1 yr; SBL Division I, n = 11, age: 20.6 ± 2.1 yr) completed four separate trials of the BJSAT with each trial consisting of shot attempts from two- and three-point distances at pre-determined court locations. Each shot attempt was scored utilising a criteria where higher scores were given when greater accuracy was exhibited. The BJSAT detected a significant, large difference in accuracy between two- and three-point shots (d = 0.99, p \u3c 0.01). Relative reliability across the repeated trials was rated as moderate for all athletes (intraclass correlation coefficient [ICC] = 0.71, p \u3c 0.01) and goodfor the SBL athletes (ICC = 0.78, p \u3c 0.01). Absolute reliability for all athletes was above the acceptable benchmark (coefficient of variation = 16.2%); however superior to skill tests available in the literature. In conclusion, the BJSAT is sensitive to two- and three-point shooting accuracy and can reliably assess jump shooting accuracy in basketball athletes
The effects of maturational variation on the performance of young Australian footballers and their selection into the Australian Football League\u27s Talent Pathway
Traditional player development pathways share a common goal, to identify and accelerate the development of talented adolescent players for senior competition. Players who gain selection into development programs gain greater access to experienced coaches, training facilities, support staff and competition. However, despite such advantages, research has shown that few players who gain initial selection into development pathways progress into professional senior competition. A major factor which potentially contributes to poor player retention in development pathways is the initial misidentification of talented athletes due to variations in biological maturity.
Earlier maturing individuals have been shown to be at a physical advantage over their later maturing counterparts in traditional talent identification testing measures. While inconclusive, some research has also indicated that more mature individuals also demonstrate technical skill advantages. It is currently unknown if coaches’ perceptions of skill and potential favour earlier biologically maturing adolescent players. Performance advantages experienced by earlier maturing adolescent players likely results in selection advantages in highly competitive player development pathways, such as the Australian Football League’s Talent Pathway (AFL TP). The broad aim of this thesis was to examine the impact of maturational variation on player performance and selection in the Under 16 (U16) stage of the AFL TP.
Chapter two of this thesis investigated the developmental efficiency of the AFL TP by examining retrospective pathway involvement of players drafted into professional teams between the 2006-2012 seasons. A secondary analysis was conducted to examine the relative age of players selected into each stage of the AFL TP (U16, U18 and Draft). The results from chapter two revealed that only 27.7% of players drafted to professional teams had participated in the initial U16 stage of the AFL TP. Further, only half of the professionally selected players had any involvement in either underage level of the AFL TP. Birth distributions at every pathway stage was biased towards relatively older players however, relatively older players were also more likely to be de-selected as the pathway progressed. Results of this study demonstrate that variations in relative age between players in the AFL TP are likely to impact on pathway efficiency and long-term development outcomes.
The results of chapter two demonstrated that selection into the AFL TP may be biased by advantages associated with the relative age of the athletes and a potential effect of maturational variation. In Australian football, maturational variation in age matched players has been shown to impact on anthropometric and physical performance measures however, the effects of maturational variation on technical skill has yet to be explored. Further, the effects of maturational variation on coaches’ perceptions of skill and potential is unknown. Chapter three investigated the inter-rater reliability and validity of two technical skill assessments commonly used by the AFL. Results from this study led to the conclusion that the AFL’s skill tests were appropriate for use in subsequent studies within this thesis.
The results of chapter four highlight that earlier maturing U16 Australian footballers are significant taller and heavier than their later maturing counterparts. Earlier maturing players also possessed greater vertical jump and sprint capacities. Interestingly, no difference was found between maturational groups and performance in technical skill tests. Chapter four and five also explored the links between maturational variation and coaches’ perceptions of skill and long-term potential. The results of the analyses in chapter four demonstrate that earlier maturing individuals are perceived to possess better marking and ball winning abilities, as well as superior overall technical skills. Chapter five highlighted that coaches’ perceptions of later maturing players were significantly lower than earlier maturing individuals, with 72% of the later maturing individuals perceived by coaches to not progress further than adolescent competition. Thus, the findings of chapter four and five suggest
that because of physical advantages and favourable coaches’ perceptions, earlier maturing Australian footballers are likely to be at a selection advantage at the U16 level of the AFL TP.
Chapter six sought to compare biological maturation, anthropometric, physical and technical skill measures between talent identified and non-talent identified junior Australian footballers at the U16 stage of the AFL TP. Twenty-five talent identified (selected into the U16 stage of the AFL TP), and twenty-five non-talent identified players (non-selected) were examined. Results demonstrated that talent identified players were more mature than their non-talent identified counterparts. Further, talent identified players were also taller, performed better in dynamic vertical jump tests and scored higher in the AFL’s handball test. Predictive modelling correctly identified 84% of the talent identified and 76% of the non-talent identified players and included the measures of standing height, dynamic vertical jump off the non-dominant foot and handball test performance. The results of chapter six further highlight the problem maturational variation presents to talent identification in adolescent Australian football, as the key discriminators of height and jumping measures have been shown in chapter four to be influenced by biological maturity.
In conclusion, this thesis highlights the poor developmental efficiency of the AFL TP which may in-part be attributed to the selection of more mature adolescent athletes in early stages of the pathway. Results from chapters four and five demonstrate that as well as being at a physical advantage, coaches also perceived earlier maturing adolescent Australian footballers to possess superior technical skills and greater long-term potential. Methods to minimise the impact of maturational variation and promote greater developmental efficiencies in the AFL TP, such as the mandatory inclusion of maturational assessments and other performance tests unaffected by maturational variation, are discussed in the concluding chapter of this thesis
Inter-rater reliability and validity of the Australian football league’s kicking and handball tests
Talent identification tests used at the Australian Football League’s National Draft Combine assess the capacities of ath-letes to compete at a professional level. Tests created for the National Draft Combine are also commonly used for talent identification and athlete development in development path-ways. The skills tests created by the Australian Football League required players to either handball (striking the ball with the hand) or kick to a series of 6 randomly generated targets. Asses-sors subjectively rate each skill execution giving a 0-5 score for each disposal. This study aimed to investigate the inter-rater reliability and validity of the skills tests at an adolescent sub-elite level. Male Australian footballers were recruited from sub-elite adolescent teams (n = 121, age = 15.7 ± 0.3 years, height = 1.77 ± 0.07 m, mass = 69.17 ± 8.08 kg). The coaches (n = 7) of each team were also recruited. Inter-rater reliability was as-sessed using Inter-class correlations (ICC) and Limits of Agreement statistics. Both the kicking (ICC = 0.96, p \u3c .01) and handball tests (ICC = 0.89, p \u3c .01) demonstrated strong relia-bility and acceptable levels of absolute agreement. Content validity was determined by examining the test scores sensitivity to laterality and distance. Concurrent validity was assessed by comparing coaches’ perceptions of skill to actual test outcomes. Multivariate analysis of variance (MANOVA) examined the main effect of laterality, with scores on the dominant hand (p = .04) and foot (p \u3c .01) significantly higher compared to the non-dominant side. Follow-up univariate analysis reported signifi-cant differences at every distance in the kicking test. A poor correlation was found between coaches’ perceptions of skill and testing outcomes. The results of this study demonstrate both skill tests demonstrate acceptable inter-rater reliable. Partial content validity was confirmed for the kicking test, however further research is required to confirm validity of the handball test
Reliability of mechanical sprint profiles in state U16 female basketball athletes
BLUF: Mechanical sprint characteristics produce acceptable trial to trial reliability in state U16 female basketball athletes.
INTRODUCTION: Sprint acceleration is a key component of basketball performance that occurs frequently during competition that is commonly measured over various distances using timing gates. Sprint profiling is a topical area of research that provides practitioners an insight into the underlying mechanical characteristics that contributed to the performance. These include theoretical maximal force, theoretical maximal velocity, maximum power, slope of the force velocity relationship, maximum ratio of force, decrease in ratio of force and max speed. This study aimed to investigate the reliability of mechanical sprint characteristics in state U16 female basketball athletes
Literature Review: Anthropometric, strength and physical capacities of senior and junior Australian footballers
This study demonstrates that senior Australian Football players are heavier and possess superior strength characteristics without any meaningful difference in aerobic capacities when compared to under 18 players.
The aim of this study was to compare the anthropometric and physical characteristics of state based junior and senior Australian Football (AF) players. Thirty-One League (age 23.7 ± 2.6 years), 19 Development League (DL) (age 20.5 ± 1.9 years), and 34 Under 18 (U18) players (age 17.4 ± 0.7 years) were recruited from a single AF club. Assessments included height and mass, upper body (bench press and weighted pull-up) and lower body (squat) three repetition max strength, lower body power (vertical jump) and 3 x 1-kilometre time trial. Multivariate analysis with Bonferroni post hoc tests were used to examine the differences between grades and position. Cohen’s d statistic was used to assess the magnitude of difference. Significant age and body mass differences were evident between all three grades (p\u3c0.01) and large to moderate differences were evident between League and U18 players in the absolute and relative bench press and back squat characteristics. No significant difference between time trial performance was evident between grades. The results demonstrate a particular need to ensure programs develop both absolute and relative strength in younger players to prepare them to compete safely and successfully in senior competitions
Operation of the Basketball Jump Shooting Accuracy Test: Intra- and inter-rater reliability of scoring procedures and floor and ceiling effects for test performance
The purpose of this study was to determine the intra- and inter-rater reliability of scoring procedures used in the newly developed Basketball Jump Shooting Accuracy Test (BJSAT) and assess for floor and ceiling effects in test performance. Thirty-one semi-professional basketball athletes completed four trials of the BJSAT. The BJSAT contains one jump shot at eight different locations, equally distributed across two- and three-point shots. Intra-rater reliability was determined by assessing the level of agreement between scores live in-person and watching captured video by the same assessor. Inter-rater reliability was determined by examining the level of agreement between two assessors who separately scored the BJSAT while watching captured video. Descriptive statistics and Cohen’s kappa (κ) were calculated to quantify the intra- and inter-rater reliability of the BJSAT. Floor and ceiling effects in scoring outcomes were analyzed to evaluate the suitability of the BJSAT. Significance for the study was set at p \u3c0.05. Intra-rater reliability demonstrated an almost perfect (κ = 0.85, p \u3c0.01) agreement between scores (12.6 ± 2.5 vs. 13.1 ± 2.8). The agreement for inter-rater reliability was rated as substantial (12.3 ± 2.5 vs. 13.5 ± 2.9, κ = 0.70, p \u3c0.01). Floor and ceiling effects were absent in the BJSAT indicating the assessment is suitable for semi-professional basketball athletes. The BJSAT is an assessment where one or multiple assessors can reliably score shooting performance for functions including player monitoring, to assess the efficacy of interventions aimed at improving skills and to assist with team selection across the season
Breaking down the barriers: Strength training in long distance triathletes
INTRODUCTION: Long distance triathletes complete large endurance training volumes with approximately half reporting to including some form of strength training (ST) in their program. However, the characteristics of this ST is currently unknown. Despite not all triathletes incorporating ST, research indicates that the completion of concurrent strength and endurance training in runners, cyclists and short course triathletes can significantly improve cycling and running economy and potentially reduce injury occurrence, likely resulting in performance improvements. Previous research has hypothesised barriers to ST in endurance athletes, however there is no empirical evidence to support such hypotheses. Therefore the primary aims of this investigation were to identify perceived barriers towards the completion of ST in long distance triathletes and ST characteristics. It was hypothesised that long distance triathletes would report limited time available for ST and fear of hypertrophy limiting their endurance performance as primary barriers to ST completion
COVID-19 trajectories among 57 million adults in England: a cohort study using electronic health records
BACKGROUND:
Updatable estimates of COVID-19 onset, progression, and trajectories underpin pandemic mitigation efforts. To identify and characterise disease trajectories, we aimed to define and validate ten COVID-19 phenotypes from nationwide linked electronic health records (EHR) using an extensible framework.
METHODS:
In this cohort study, we used eight linked National Health Service (NHS) datasets for people in England alive on Jan 23, 2020. Data on COVID-19 testing, vaccination, primary and secondary care records, and death registrations were collected until Nov 30, 2021. We defined ten COVID-19 phenotypes reflecting clinically relevant stages of disease severity and encompassing five categories: positive SARS-CoV-2 test, primary care diagnosis, hospital admission, ventilation modality (four phenotypes), and death (three phenotypes). We constructed patient trajectories illustrating transition frequency and duration between phenotypes. Analyses were stratified by pandemic waves and vaccination status.
FINDINGS:
Among 57 032 174 individuals included in the cohort, 13 990 423 COVID-19 events were identified in 7 244 925 individuals, equating to an infection rate of 12·7% during the study period. Of 7 244 925 individuals, 460 737 (6·4%) were admitted to hospital and 158 020 (2·2%) died. Of 460 737 individuals who were admitted to hospital, 48 847 (10·6%) were admitted to the intensive care unit (ICU), 69 090 (15·0%) received non-invasive ventilation, and 25 928 (5·6%) received invasive ventilation. Among 384 135 patients who were admitted to hospital but did not require ventilation, mortality was higher in wave 1 (23 485 [30·4%] of 77 202 patients) than wave 2 (44 220 [23·1%] of 191 528 patients), but remained unchanged for patients admitted to the ICU. Mortality was highest among patients who received ventilatory support outside of the ICU in wave 1 (2569 [50·7%] of 5063 patients). 15 486 (9·8%) of 158 020 COVID-19-related deaths occurred within 28 days of the first COVID-19 event without a COVID-19 diagnoses on the death certificate. 10 884 (6·9%) of 158 020 deaths were identified exclusively from mortality data with no previous COVID-19 phenotype recorded. We observed longer patient trajectories in wave 2 than wave 1.
INTERPRETATION:
Our analyses illustrate the wide spectrum of disease trajectories as shown by differences in incidence, survival, and clinical pathways. We have provided a modular analytical framework that can be used to monitor the impact of the pandemic and generate evidence of clinical and policy relevance using multiple EHR sources.
FUNDING:
British Heart Foundation Data Science Centre, led by Health Data Research UK
What\u27s the Deal with Water
Affordable natural disaster kits and water filters are not economically efficient or accessible to those who are in need of it. We want to create an affordable kit with a specially designed water filter to help provide clean water to those in a water crisis. This problem is important to solve because large-scale natural disasters around the world are affecting people every day. According to the EPA clean water is essential to our health, communities, and economies. Natural disasters, on average, affect over 100 million people per year globally so this is clearly an issue that can still be worked on