Application of non-parametric correlations to compare the compliance of Beighton and Sachse tests in the assessment of hypermobility based on research of the fitness instructors group

Abstract

BackgroundJoint hypermobility is a spectrum of symptoms associated with connective tissue disorders. The main feature is the increased range of joint mobility. Hypermobility is rarely recognised in clinical practice. The diagnosis is based on the evaluation of diagnostic tests, mainly the Beighton score. The divergence of research methods means that patients do not receive a proper diagnosis and treatment. MethodsThe study used the Beighton score and the Sachse scale. Both tests are “all-or-none-tests”. Non-parametric correlations were used to assess the concordance effect. To this end, two methods were adopted, i.e., the Spearman Rank Correlation and Kendall tau Rank Correlation. The values of correlation coefficients were calculated, respectively, rho and Kendall tau. The study involved 30 women working as fitness instructors. ResultsConsent results of hypermobility assessment for both methods were obtained in 3 cases, while the discrepancy in the hypermobility statement concerns measurements made in 10 participants. This cursory assessment already indicates a significant differentiation of results obtained for both methods. DiscussionTo the best of our knowledge, there are not many studies comparing different HSD diagnostic methods. The Beighton score is the most commonly used, but the selection of only 5 joints for the examination does not show the systemic nature of hypermobility. A reliable methodology should be based not only on goniometric measurements of selected joints. ConclusionThe expanded correlation analysis of Beighton and Sachse hypermobility tests indicates their poor compliance. Therefore, there is a need to standardise hypermobility spectrum disorder diagnostics, which may affect the objectification and credibility of these diagnostics.