Is the freezing index a valid outcome to assess freezing of gait during turning in Parkinson’s disease? - Goris, Maaike; Ginis, Pieter; Hansen, Clint; Schlenstedt, Christian; Hausdorff, Jeffrey M.; D’Cruz, Nicholas; Vandenberghe, Wim; Maetzler, Walter; Nieuwboer, Alice; Gilat, Moran (Frontiers in Neurology, 2025)