Clinimetrics of the Freezing of Gait Questionnaire for Parkinson Disease During the “off” State

Abstract

Introduction: Freezing of gait, a common PD motor symptom, could increase the risk of falling. This study aimed to investigate the clinimetric attributes of the Freezing of Gait Questionnaire (FOGQ) for people with Parkinson disease in the “off” state. Methods: A total of 115 patients with Parkinson disease (PD; mean age, 60.25 years) were included. Acceptability, internal consistency (by the Cronbach alpha, and test-retest by Intraclass Correlation [ICC]), and reliability of the Persian-translated version of the FOGQ were examined. Dimensionality was estimated by Exploratory Factor Analysis (EFA). Fall efficacy scale-international, unified Parkinson disease rating scale-II, Berg balance scale, functional reach test, and Parkinson disease questionnaire-39 were applied to determine the convergent validity. Diagnostic accuracy for obtaining optimal cutoff point, separating faller and non-faller groups, was analyzed by Receiver Operating Characteristics (ROC) curve analysis and Area Under the Curve (AUC). All tests were carried out in an “off” state. Results: The Cronbach alpha was high (α=0.92). The test-retest showed high reliability (ICC=0.89). The FOGQ was unidimensional according to the EFA and had acceptable convergent validity with moderate to high correlation with other clinical scales. The optimal cutoff point to discriminate fallers from non-fallers during the “off” state was 9/10, with an AUC of 0.92. Conclusion: Our results suggest that the FOGQ has appropriate reliability, validity, and discriminative ability for measuring FOG in patients with PD during the “off” state.

Parkinson’s disease patients show delayed hemodynamic changes in primary motor cortex in fine motor tasks and decreased resting-state interhemispheric functional connectivity: a functional near-infrared spectroscopy study

“… 3 Freezing of gait severity was assessed with the freezing of gait questionnaire (FOGQ). 24 All evaluations detailed in this study were conducted while the subjects were in their “off” medication state ( after the last anti-parkinsonian medication dose was taken). The MDS-UPDRS part III scores were additionally validated by an independent rater.…”

“…A neurologist (FJRR) used the Hoehn and Yahr (HY) scale 23 and the Movement Disorder Society-Sponsored Revision of the Unified Parkinson Disease Rating Scale (MDS-UPDRS, part III) to determine the severity of the disease 3 . Freezing of gait severity was assessed with the freezing of gait questionnaire (FOGQ) 24 . All evaluations detailed in this study were conducted while the subjects were in their “off” medication state (∼12 h after the last anti-parkinsonian medication dose was taken).…”