TENDINopathy Severity Assessment – Achilles (TENDINS-A): Development and Content Validity Assessment of a New Patient-Reported Outcome Measure for Achilles Tendinopathy
Myles Murphy, Richard Newsham‐West, Jill Cook, Ruth L. Chimenti, Robert‐Jan de Vos, Nicola Maffulli, Peter Malliaras, Nonhlanhla Sharon Mkumbuzi, Craig Purdam, J. Turner Vosseller, Ebonie Rio
Abstract
OBJECTIVE: To develop a new patient-reported outcome measure (PROM) assessing TENDINopathy Severity of the Achilles (TENDINS-Achilles) and evaluate its content validity. DESIGN: Mixed-methods, modified Delphi. METHODS: We performed 1 round of semistructured one-on-one interview responses with professionals and patients, for initial item generation. This was followed by 1 round of survey responses for professionals and a final round of semistructured one-on-one interviews with patients. The work culminated in a PROM to quantify Achilles tendinopathy severity under the core health domain of disability. Participants identified 3 subdomains contributing to the severity of disability of Achilles tendinopathy: pain, symptoms, and functional capacity. RESULTS: All 8 patient participants invited to participate were enrolled. Forty professional participants (50% women, six different continents) were invited to participate and 30 were enrolled (75% response rate). Therefore, a total of 30 professionals and 8 patients were included within this study. Following 3 rounds of qualitative or quantitative feedback, this study has established the content validity of TENDINS-A (good relevance, comprehensibility, and comprehensiveness) as a new PROM to assess the severity of Achilles tendinopathy, which assesses aspects of pain, symptoms, and functional capacity. CONCLUSION: TENDINS-A has established content validity and is appropriate for use with clinical and research populations. We recommend users interpret TENDINS-A results cautiously, until further testing evaluates the most appropriate scoring scale, reliability, construct validity, criterion validity, and responsiveness of TENDINS-A. Until these psychometric properties are established, we suggest using TENDINS-A alongside existing tools. J Orthop Sports Phys Ther 2024;54(1):70-85. Epub 24 August 2023. doi:10.2519/jospt.2023.11964