Beyond the Diagnosis: Using Patient Characteristics and Domains of Tendon Health to Identify Latent Subgroups of Achilles Tendinopathy.

The study was cross-sectional and used baseline data, so it cannot show how patients recover or which treatment works. The subgroup solution was not clear-cut: some fit tests suggested two subgroups, while the authors chose three. The Structure-dominant subgroup was small (n=22), which makes its profile harder to trust. The classification model was built after the subgroup analysis and was not cross-validated in another sample. Missing data reduced the number of usable predictor combinations, especially for the Structure-dominant subgroup. Patients may fit more than one subgroup in practice, and clinical judgment should not be replaced by the model. The variables were limited to those collected in the parent studies, so other factors may define additional subgroups. The authors noted that additional subgroups might exist in youth and elite athletes or other cohorts not represented.

The authors declared no financial disclosure or conflict of interest.

Do not use these subgroups to choose a specific treatment. The study did not test treatment effects, and the classification model was developed after the analysis and was not cross-validated.