INTRA AND INTER-RATER RELIABILITY IN DYNAMIC VALGUS IN SOCCER PLAYERS

Introduction: The two-dimensional (2D) methods of dynamic assessment of knee valgus are popular because of their low cost and the fact that they are easy to implement. It is believed that dynamic valgus of the knee is one of the main disorders responsible for non-contact lesions of the anterior cruciate ligament. There are two categories of reliability with regard to data collectors: inter-rater (reliability among multiple data collectors) and intra-rater (reliability of a single data collector). Objectives: To assess intra and inter-rater reliability during the step-down test in professional soccer athletes, using initial and final angles for each test repetition. Methods: The sample consisted of 29 professional soccer players. All study participants were considered by club physiotherapists to be free of any musculoskeletal injury and were performing daily training tasks. Two male evaluators participated in the study. Results: For each data group, mean and standard deviation were determined. The intra- and inter-rater reliability of all data was determined using the intraclass correlation coefficient (ICC), with a confidence interval of 95% and alpha of p <= 0.05. Rater 1 was classified in the first intra-rater stage of the analysis for heel touch, with good to excellent reliability. For the inter-rater analysis, both for heel touch and for greater valgus angle, there was excellent reliability among the raters. Conclusion: It was concluded that there is high inter-rater and intra-rater reliability through two-dimensional analysis using the Step Down Test in professional soccer athletes.