Development of the Italian version of the trunk impairment scale in subjects with acute and chronic stroke. Cross-cultural adaptation, reliability, validity and responsiveness.

Purpose: To cross-culturally adapt and psychometrically analyse the Italian version of the Trunk Impairment Scale on acute (cohort 1) and chronic stroke patients (cohort 2).

Methods: The Trunk Impairment Scale was culturally adapted in accordance with international standards. The psychometric testing included: internal consistency (Cronbach's alpha), inter- and intra-rater reliability (intraclass correlation coefficient; standard error of measurement and minimal detectable change), construct validity by comparing Trunk Impairment Scale score with Barthel Index, motor subscale of Functional Independence Measure, and Trunk Control Test (Pearson's correlation), and responsiveness (Effect Size, Effect Size with Guyatt approach, standardized response mean, and Receiver Operating Characteristics curves).