The aim of this study was to translate the Foot Impact Scale for RA (FIS-RA) to the Dutch target language and to evaluate its internal construct validity using Rasch analysis. Forward and backward translations of the original English version of the FIS-RA scale, combined with synthesis techniques and expert committee review, were undertaken to produce a final Dutch version with two subscales for impairment/footwear (FIS-RAIF) and activity/participation (FIS-RAAP). The pre-final version was field tested in RA patients to investigate face and content validity. FIS-RA questionnaires were completed by 207 Dutch RA patients. Rasch analysis tested the data for overall fit to the model, item and person fit, unidimensionality, differential item function (DIF) by age, gender and disease duration, targeting, reliability and local response dependency.
- rheumatoid arthritis
- foot impact scale