Validation of the Brazilian version of the patient-determined disease steps scale in persons with multiple sclerosis

•Scores from the Brazilian version of PDDS/BR were validated in persons with MS.•The relationship between PDDS/BR and EDSS scores was strong.•Comparable associations between the PDDS/BR and EDSS with TUG, T25FW, 6MWT and 9HPT.•PDDS/BR scores provide a valid and reliable assessment of disability status. The present study translated and adapted the Brazilian version of the Patient-Determined Disease Steps (PDDS) scale and tested its validity and reproducibility in Brazilian persons with multiple sclerosis (MS). The PDDS underwent translation and back-translation procedures for producing a Brazilian Portuguese version of the PDDS (PDDS/BR). Sixty-three patients with MS (48 females) completed the PDDS/BR and underwent a neurological examination for generation of Expanded Disability Status Scale (EDSS) scores. Participants further performed the following tests: Timed 25-Foot Walk (T25FW), Timed Up and Go (TUG), six-minute walk test (6MWT), Nine Hole Peg (9HPT), and Symbol Digit Modalities Test (SDMT). Construct validity of PDDS/BR scores was determined by Spearman correlation with EDSS, and comparison of correlations between PDDS/BR and EDSS with the functional tests. We examined overall correct classification of disability categories (i.e., mild, moderate, or severe disability) by the PDDS/BR in relation to the EDSS. Test-retest reproducibility of PDDS/BR scores was examined in a subsample of 31 participants after 15 days. There was a strong relationship between the PDDS/BR and EDSS scores (ρ = 0.723, p