Cross cultural adaptation of the TENDINopathy severity assessment - Achilles (TENDINS-A) for Spanish speaking populations.

Only 37% of the sample were actively seeking care for Achilles tendinopathy; the rest were recruited online, so the sample may not reflect patients in a clinical setting. All data were collected via online surveys; the authors note the questionnaire may perform differently when administered in person. The Pain sub-score had notably lower internal consistency (person reliability 0.45) than the other sub-scores, limiting confidence in that specific score. The questionnaire failed to discriminate between patients with acceptable versus unacceptable symptoms, which was a stated hypothesis and is a practical limitation for tracking treatment response. The Function sub-score correlated moderately with age (r=0.4), so age differences may partly drive score differences rather than true disability differences. Control groups were small (19 foot pain, 17 pain-free), limiting how well the discrimination findings generalise. The translation represents North American and European Spanish; the authors acknowledge it may not fully capture the linguistic diversity of all 30+ Spanish-speaking countries.

All authors declare no competing interests. No funding source is named in the text provided.

Do not read the overall 'validated' conclusion as meaning every sub-score is equally robust. The Pain sub-score had a person reliability of only 0.45, well below the 0.70 threshold the authors set, and the questionnaire failed to separate patients who consider their symptoms acceptable from those who do not (p=0.24 for the Total score). If you use the Pain sub-score to track a patient's progress or to decide whether symptoms have resolved, you are relying on the weakest part of the instrument.