title: Detecting freezing of gait with a tri-axial accelerometer in Parkinson's disease patients.
abstract: Freezing of gait (FOG) is a common motor symptom of Parkinson's disease (PD), which presents itself as an inability to initiate or continue gait. This paper presents a method to monitor FOG episodes based only on acceleration measurements obtained from a waist-worn device. Three approximations of this method are tested. Initially, FOG is directly detected by a support vector machine (SVM). Then, classifier's outputs are aggregated over time to determine a confidence value, which is used for the final classification of freezing (i.e., second and third approach). All variations are trained with signals of 15 patients and evaluated with signals from another 5 patients. Using a linear SVM kernel, the third approach provides 98.7% accuracy and a geometric mean of 96.1%. Moreover, it is investigated whether frequency features are enough to reliably detect FOG. Results show that these features allow the method to detect FOG with accuracies above 90% and that frequency features enable a reliable monitoring of FOG by using simply a waist sensor.
authors.affiliation: neusta mobile solutions GmbH (NMS), Konsul-Smidt-Str. 24, 28217, Bremen, Germany. claasahl@tzi.de.
authors.forename: Claas
authors.initials: C
authors.lastname: Ahlrichs
authors.affiliation: Technical Research Centre for Dependency Care and Autonomous Living(CETpD), Universitat Politcnica de Catalunya, Vilanova i la Geltr, Spain.
authors.forename: Albert
authors.initials: A
authors.lastname: Samà
authors.affiliation: Institute for Artificial Intelligence (AGKI), University of Bremen, Bremen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Lawo
authors.affiliation: Technical Research Centre for Dependency Care and Autonomous Living(CETpD), Universitat Politcnica de Catalunya, Vilanova i la Geltr, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Cabestany
authors.affiliation: Technical Research Centre for Dependency Care and Autonomous Living(CETpD), Universitat Politcnica de Catalunya, Vilanova i la Geltr, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rodríguez-Martín
authors.affiliation: Technical Research Centre for Dependency Care and Autonomous Living(CETpD), Universitat Politcnica de Catalunya, Vilanova i la Geltr, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Pérez-López
authors.affiliation: Electrical & Electronic Engineering Department, NUI Galway, Galway, Ireland.
authors.forename: Dean
authors.initials: D
authors.lastname: Sweeney
authors.affiliation: Electrical & Electronic Engineering Department, NUI Galway, Galway, Ireland.
authors.forename: Leo R
authors.initials: LR
authors.lastname: Quinlan
authors.affiliation: Electrical & Electronic Engineering Department, NUI Galway, Galway, Ireland.
authors.forename: Gearòid Ò
authors.initials: GÒ
authors.lastname: Laighin
authors.affiliation: School of Medicine, NUI Galway, Galway, Ireland.
authors.forename: Timothy
authors.initials: T
authors.lastname: Counihan
authors.affiliation: School of Medicine, NUI Galway, Galway, Ireland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Browne
authors.affiliation: Maccabi Healthcare Services, Tel Aviv, Israel.
authors.forename: Lewy
authors.initials: L
authors.lastname: Hadas
authors.affiliation: Maccabi Healthcare Services, Tel Aviv, Israel.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Vainstein
authors.affiliation: IRCCS Fondazione Santa Lucia, Rome, Italy.|Niccolò Cusano University of Rome, Rome, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Costa
authors.affiliation: IRCCS Fondazione Santa Lucia, Rome, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Annicchiarico
authors.affiliation: Unidad de Parkinson y trastornos del movimiento (UParkinson), Barcelona, Spain.
authors.forename: Sheila
authors.initials: S
authors.lastname: Alcaine
authors.affiliation: Unidad de Parkinson y trastornos del movimiento (UParkinson), Barcelona, Spain.
authors.forename: Berta
authors.initials: B
authors.lastname: Mestre
authors.affiliation: Unidad de Parkinson y trastornos del movimiento (UParkinson), Barcelona, Spain.
authors.forename: Paola
authors.initials: P
authors.lastname: Quispe
authors.affiliation: Unidad de Parkinson y trastornos del movimiento (UParkinson), Barcelona, Spain.
authors.forename: Àngels
authors.initials: À
authors.lastname: Bayes
authors.affiliation: Electrical & Electronic Engineering Department, NUI Galway, Galway, Ireland.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Rodríguez-Molinero
mesh_terms: D061725:Accelerometry / Q000379:methods*; D005684:Gait; D006801:Humans; D000069550:Machine Learning; D010300:Parkinson Disease / Q000503:physiopathology*; D060388:Support Vector Machine
keywords: Freezing of Gait; Machine learning; Parkinson’s disease; Support vector machines