The validation of an Italian version of the Freezing of Gait Questionnaire

Freezing of gait (FOG) is a common and disabling symptom in Parkinson’s disease (PD) and its staging is complex because of its episodic nature. Patient-reported assessments are essential in evaluating this disabling symptom. The Freezing of Gait Questionnaire (FOG-Q) is considered a valid and reliable tool for the assessment of FOG severity. The aim of our study was to validate the Italian version of FOG-Q and to investigate for its association with several clinical aspects of PD. Fifty-one PD patients were administered the FOG-Q and the timed up and go test. Moreover, patients were evaluated for the unified PD rating scale (UPDRS), the Hoehn and Yahr Scale (H&Y) and the falls-efficacy scale [FES(S)]. Mean (SD) FOG-Q item scores ranged between 1.5 and 2.7 (1.0–1.4); corrected item–total correlations ranged between 0.63 and 0.86. The total FOG-Q score ranged between 0 and 24, with a mean + SD of 12.6 (6.2) and a median (q1–q3) of 12 (9–17). Reliability was 0.91. FOG-Q correlated with H&Y (0.36, p = 0.0091), UPDRS part III (rS = 0.27, p = 0.054), PD duration (rS = 0.35, p < 0.01), FES(S) (rS = 0.58, p < 0.001) and the timed up and go test (rS = 0.51, p = 0.001). Non-significant positive correlations were observed for dyskinesia and motor fluctuations. Our study validates the Italian version of the FOG-Q, in that it results being a reliable instrument for assessing FOG in PD patients.