Frenchay dysarthria assessment (FDA-2) in Parkinson's disease: cross-cultural adaptation and psychometric properties of the European Portuguese version.

Hypokinetic dysarthria is a common symptom in those with Parkinson's disease (PD); there is currently no standardized or validated tool for assessing speech in this population. To translate into European Portuguese (EP) the FDA-2 and perform a cultural adaptation followed by an evaluation of its psychometric properties in PD in a sample of people with PD in different stages of disease progression. Translation, back-translation, experts' analysis, pre-test and final version test were performed. The EP version of the FDA-2 was administered to 80 people with PD (PwP) with dysarthria, feasibility and acceptability, reliability (internal consistency and inter-rater reliability) and validity (face and convergent) were measured. Overall, the EP-FDA-2 proved to be similar to the original demonstrating the same conceptual meanings, semantics, idiomatic and score equivalences. It has good feasibility (missing data <5 %), acceptability (ceiling and floor effects <15 %), a high reliability of the total score (0.94), an excellent inter-rater agreement for the total score (0.96) and moderate to large construct validity for 81 % of its items. It is well correlated with the gold standard for disease severity assessment in PD, the MDS-UPDRS. The EP-FDA-2 has shown the salient features of a valid tool that can be used by speech and language therapists in the assessment of dysarthria in PD in clinical practice as in the research field.