Brazilian version of the Functional Arm Scale for Throwers (FAST): Translation and cross-cultural adaptation

Assessment of shoulder function in throwing athletes using valid instruments is important for appropriate rehabilitation. However, no instruments specifically designed for throwers exist in Brazilian Portuguese. The Functional Arm Scale for Throwers (FAST) is a widely used instrument to evaluate shoulder function, but it has not yet been adapted for use with Brazilian athletes.

To translate and culturally adapt the FAST for use in Brazil.

The process followed standardized guidelines for translation and cultural adaptation: translation, synthesis, back-translation, expert committee review, and pre-testing with throwing athletes experiencing shoulder pain, who trained at least three times per week, and with competition experience. These procedures ensured idiomatic, semantic, conceptual, and experiential equivalences. Athletes evaluated item clarity and suggested revisions when necessary. Items with over 90% comprehension were considered adequate.

The pre-test included 37 athletes (24 court handball, 11 beach handball, 2 water polo; mean age 24.76 ± 8.52 years). Minor modifications improved clarity and cultural relevance. For example, "baseball or softball" was replaced with "your sport," and baseball-specific terms such as "long toss" and "bullpen sessions" were adapted using terminology familiar to Brazilian athletes. All items achieved over 90% comprehension.

The FAST was successfully translated and culturally adapted for Brazilian Portuguese. This instrument provides clinicians with a valid tool to assess and monitor upper limb function in throwing athletes during rehabilitation and offers researchers a standardized instrument for investigating shoulder function in this population. The adapted version showed high comprehensibility, and future studies should assess its measurement properties.