Cross-cultural adaptation of the Functional Ambulation Categories (FAC) in Danish patients with acquired brain injury

Purpose The Functional Ambulation Categories (FAC) is a measurement tool used to classify walking ability according to the amount of physical support required. In this study, the FAC is translated into Danish and the reliability and validity of the FAC are established in a population of patients with acquired brain injury (ABI).Methods The study took place in a neuro-rehabilitation setting. The translation process followed an accepted forward-backward translation method in six steps. For the assessment of clinometric properties a cross-sectional study design was applied. Interrater reliability was assessed with weighted Cohen's kappa. Construct validity of the FAC was assessed with Spearman's rho by correlating the FAC to walking velocity assessed with the 10-meter walk test and to the number of daily steps assessed with accelerometers.Results The FAC was successfully translated into Danish. For the assessment of clinometric properties, 53 patients were included. Almost perfect interrater reliability was found (kappa = 0.92, p < 0.0001). Construct validity was high between FAC and walking velocity (r(2) = 0.87, p < 0.0001) and moderate between FAC and the number of daily steps (r(2) = 0.62, p < 0.0001).Conclusion The Danish version of the FAC was found reliable and valid for use in-patients with ABI.