Validation and reliability of the Spanish version of the Function in Sitting Test (S-FIST) to assess sitting balance in subacute post-stroke adult patients.

BACKGROUND: Function in Sitting Test (FIST) is a clinical functional assessment of sitting balance validated in adults with stroke. For a major use of this, the test is recommended to be translated in Spanish-speaking countries.

OBJECTIVES: Translate to Spanish the FIST and determine its intra-rater and inter-rater reliabilities and concurrent validity as a measure of sitting balance in adult individuals with stroke.

METHODS: The original version was translated into Spanish and was agreed by a team of experts. A back-translation into English was subsequently performed and sent to the original author, who approved this version named from now Spanish version of Function in Sitting Test (S-FIST). Sixty post-stroke patients' performance was recorded on a videotape. These videos were then used to carry out four measurements to assess the intra-rater and inter-rater reliabilities; two of these were performed by the same rater and the third and fourth by a second and third rater.

RESULTS: The S-FIST meets the following requirements: good construct validity and high correlation with Spanish version of Trunk Impairment Scale 2.0 (S-TIS 2.0) scores (r = 0.791) Spearman's rank, high internal consistency (Cronbach's α-coefficient = 0.97), and high intra-rater and inter-rater reliabilities for the summed scores assessed by intra-class correlation coefficient were 0.999 and 0.997, respectively.

CONCLUSIONS: The S-FIST is valid and reliable and can be recommended for use in the evaluation of dynamic and sitting balance and trunk control in future research and clinical practice on post-stroke patients. Guidelines for treatment and level of quality of trunk activity can be derived from its use.