Objective: To evaluate the measurement properties of the Brazilian version of the Copenhagen Neck Functional Disability Scale (CNFDS) in patients with chronic neck pain.
Methods: One hundred and five patients were included in the study. The structural validity of the CNFDS was assessed by exploratory and confirmatory factor analysis with the following fit indices: chi-square divided by degrees of freedom (chi-square/df), root mean square error of approximation (RMSEA), comparative fit index (CFI), and Tucker-Lewis index (TLI).