Is the Landing Error Scoring System Reliable and Valid? A Systematic Review

Abstract

Context: The Landing Error Scoring System (LESS) is a clinical tool often used in research and practice to identify athletes presenting high injury-risk biomechanical patterns during a jump-landing task. Objective: To systematically review the literature addressing the psychometric properties of the LESS. Data Sources: Three electronic databases (PubMed, Web of Science, and Scopus) were searched on March 28, 2018, using the term “Landing Error Scoring System.” Study Selection: All studies using the LESS as main outcome measure and addressing its reliability, validity against motion capture system, and predictive validity were included. Original English-language studies published in peer-reviewed journals were reviewed. Studies using modified versions of the LESS were excluded. Study Design: Systematic literature review. Level of Evidence: Level 4. Data Extraction: Study design, population, LESS testing procedures, LESS scores, statistical analysis, and main results were extracted from studies using a standardized template. Results: Ten studies met inclusion criteria and were appraised using Newcastle-Ottawa Quality Assessment Scale adapted for cross-sectional studies. The overall LESS score demonstrated good-to-excellent intrarater (intraclass correlation coefficient [ICC], 0.82-0.99), interrater (ICC, 0.83-0.92), and intersession reliability (ICC, 0.81). The validity of the overall LESS score against 3-dimensional jump-landing biomechanics was good when individuals were divided into 4 quartiles based on LESS scores. The validity of individual LESS items versus 3-dimensional motion capture data was moderate-to-excellent for most of the items addressing key risk factors for anterior cruciate ligament (ACL) injury. The predictive value of the LESS for ACL and other noncontact lower-extremity injuries remains uncertain based on the current scientific evidence. Conclusion: The LESS is a reliable screening tool. However, further work is needed to improve the LESS validity against motion capture system and confirm its predictive validity for ACL and other noncontact lower-extremity injuries.

The ‘DEEP’ Landing Error Scoring System

“…The test demonstrates acceptable reliability and validity [10,11,23], as well as predictive value for non-contact ACL injury using a threshold of 5 errors [12]. The inter-rater reliability of the total LESS score is good to excellent, with ICC ranging from 0.83 to 0.92 [10,11,23] and typical errors at 0.71 LESS errors [10]. The results from the current study indicate that the typical errors from the automated processing and scoring of the LESS through computer vision when applying the random forest model (Table 2) are less than half an error greater than scores taken from two expert clinicians.…”

“…The Landing Error Scoring System (LESS) is one movement screen with demonstrated reliability [10,11] and validity [11,12]. Clinicians evaluate 2D video recordings from three double-leg drop-jump landing tasks per individual to detect 'movement errors' linked to non-contact anterior cruciate ligament (ACL) and other lower-extremity injury mechanisms [10].…”

Clinical Implications of Jump Distance on Landing Error Scoring System Scores

“…A subjective assessment of the quality of movement between initial ground contact and peak knee flexion is also considered during LESS scoring. The scientific literature and clinical community use a range of terminology to describe the jump-landing task used to score the LESS, including jumplanding [2][3][4][5] , drop-jump 6 , drop-landing 7 , and drop-vertical jump [8][9][10] . Given that the jumplanding task of the original LESS is fundamentally active in nature (i.e., requires an individual to jump forward) 1 , in contrast to the more passive nature of the drop jump task, the term jump-landing will be used to reference the jump-landing task of the LESS.…”

“…The LESS scores range from 0 to 17 errors, where a greater score indicates a greater number of landing errors, poorer landing biomechanics, and greater risk of sustaining non-contact ACL injury. A recent systematic review concluded that the LESS is a valid and reliable screening tool, however the predictive values of the LESS for ACL injury remains uncertain based on current scientific evidence 5 . More specifically, Padua et al 11 evaluated ACL injury risk in elite-youth soccer players in a prospective study and concluded that LESS scoring has a good sensitivity (86%) and acceptable specificity (64%) in identifying risk of non-contact ACL injury.…”

“…The mean difference in LESS scores between conditions for participants scored at high risk category exclusively for d 50% and d SS was 1.85 and 1.82 errors, respectively. According to studies exploring the psychometric properties of the LESS, the standard error of measurement (SEM) for intra-rater reliability is 0.19 to 0.52, inter-rater reliability is 0.71, and test-retest reliability is 0.81 errors5 . These SEM values indicate that the magnitude of the difference in LESS score between participants categorized at high risk exclusively for a given landing condition is clinically meaningful.…”