The Greek version of Shoulder Pain and Disability Index (SPADI): translation, cultural adaptation, and validation in patients with rotator cuff tear.

Background: This study aimed to translate and culturally adapt a Greek version of the Shoulder Pain and Disability Index (SPADI) questionnaire and to validate its usage in Greek patients.

Materials and methods: A forward and backward translation was performed, and the final version of the Greek questionnaire was administered to 134 outpatients (mean age 47.4 ± 14.5) with rotator cuff tear under conservative treatment. The questionnaire was re-administered 2-5 days later to assess test-retest reliability. Patients completed the Greek SPADI, the Greek version of the Quick DASH (Disability of the Arm, Shoulder and Hand Questionnaire) and the EuroQoL EQ-5D. 102 of the 134 questionnaires were considered valid.

Results: The internal consistencies of the SPADI total and its subscales measured with Cronbach's alpha coefficient were high (0.932 for SPADI-Total, 0.899 for SPADI-Disability, 0.905 for SPADI-Pain). Intraclass correlation coefficients showed excellent test-retest reliability (0.899 for Disability, 0.902 for Pain, and 0.929 for total SPADI). A significantly high positive correlation was found between the SPADI total score and its subscales, and Quick DASH for Pain and Disability. Significant correlations were also found between SPADI scales and EQ-5D variables. There was a moderate positive correlation with the variables "self-reliance" (r = 0.66), "common activities" (r = 0.58), and "pain/discomfort" (r = 0.49), and a weaker correlation with the "mobility" variable (r = 0.20). Factor analysis (PAF method) revealed a bidimensional formation of the SPADI. Eight items (five pain/three disability) weighted the first factor by >0.5, and five disability items weighted the second factor.

Conclusions: The Greek SPADI represents a valid and reliable tool for measuring pain and disability in patients with painful shoulder disorders.

Level of evidence: Level 3.