Italian cross-cultural adaptation and validation of three different scales for the evaluation of shoulder pain and dysfunction after neck dissection: University of California - Los Angeles (UCLA) Shoulder Scale, Shoulder Pain and Disability Index (SPADI) and Simple Shoulder Test (SST)

Shoulder syndrome after neck dissection is a well known entity, but its incidence and prognostic factors influencing recovery have not been clearly assessed due to the heterogeneity of possible evaluations. The University of California - Los Angeles (UCLA) Shoulder Scale, the Shoulder Pain and Disability Index (SPADI) and the Simple Shoulder Test (SST) are three English-language questionnaires commonly used to test shoulder impairment. An Italian version of these scales is not available. The aim of the present study was to translate, culturally adapt and validate an Italian version of UCLA Shoulder Scale, SPADI and SST. Translation and cross-cultural adaptation of the SPADI, the UCLA shoulder scale and the SST was performed according to the international guidelines. Sixty-six patients treated with neck dissection for head and neck cancer were called to draw up these scales. Forty patients completed the same questionnaires a second time one week after the first to test the reproducibility of the Italian versions. All the English-speaking Italian patients (n = 11) were asked to complete both the English and the Italian versions of the three questionnaires to validate the scales. No major problems regarding the content or the language were found during the translation of the 3 questionnaires. For all three scales, Cronbach's α was > 0.89. The Pearson correlation coefficient was r > 0.91. With respect to validity, there was a significant correlation between the Italian and the English versions of all three scales. This study shows that the Italian versions of UCLA Shoulder Scale, SPADI and SST are valid instruments for the evaluation of shoulder dysfunction after neck dissection in Italian patients