@article{ref1,
title="The influence of head impact threshold for reporting data in contact and collision sports: systematic review and original data analysis",
journal="Sports medicine",
year="2015",
author="King, D. and Hume, P. and Gissane, C. and Brughelli, M. and Clark, T.",
volume="46",
number="2",
pages="151-169",
abstract="BACKGROUND: Head impacts and resulting head accelerations cause concussive injuries. There is no standard for reporting head impact data in sports to enable comparison between studies. <br><br>OBJECTIVE: The aim was to outline methods for reporting head impact acceleration data in sport and the effect of the acceleration thresholds on the number of impacts reported. <br><br>METHODS: A systematic review of accelerometer systems utilised to report head impact data in sport was conducted. The effect of using different thresholds on a set of impact data from 38 amateur senior rugby players in New Zealand over a competition season was calculated. <br><br>RESULTS: Of the 52 studies identified, 42 % reported impacts using a >10-g threshold, where g is the acceleration of gravity. Studies reported descriptive statistics as mean ± standard deviation, median, 25th to 75th interquartile range, and 95th percentile. Application of the varied impact thresholds to the New Zealand data set resulted in 20,687 impacts of >10 g, 11,459 (45 % less) impacts of >15 g, and 4024 (81 % less) impacts of >30 g. <br><br>DISCUSSION: Linear and angular raw data were most frequently reported. Metrics combining raw data may be more useful; however, validity of the metrics has not been adequately addressed for sport. Differing data collection methods and descriptive statistics for reporting head impacts in sports limit inter-study comparisons. Consensus on data analysis methods for sports impact assessment is needed, including thresholds. Based on the available data, the 10-g threshold is the most commonly reported impact threshold and should be reported as the median with 25th and 75th interquartile ranges as the data are non-normally distributed. Validation studies are required to determine the best threshold and metrics for impact acceleration data collection in sport. <br><br>CONCLUSION: Until in-field validation studies are completed, it is recommended that head impact data should be reported as median and interquartile ranges using the 10-g impact threshold. Keywords: Australian football, Rugby, Soccer<p /> <p>Language: en</p>",
language="en",
issn="0112-1642",
doi="10.1007/s40279-015-0423-7",
url="http://dx.doi.org/10.1007/s40279-015-0423-7"
}