title: The modified bradykinesia rating scale for Parkinson's disease: reliability and comparison with kinematic measures.
abstract: Bradykinesia encompasses slowness, decreased movement amplitude, and dysrhythmia. Unified Parkinson's Disease Rating Scale-based bradykinesia-related items require that clinicians condense abnormalities in speed, amplitude, fatiguing, hesitations, and arrests into a single score. The objective of this study was to evaluate the reliability of a modified bradykinesia rating scale, which separately assesses speed, amplitude, and rhythm and its correlation with kinematic measures from motion sensors. Fifty patients with Parkinson's disease performed Unified Parkinson's Disease Rating Scale-directed finger tapping, hand grasping, and pronation-supination while wearing motion sensors. Videos were rated blindly and independently by 4 clinicians. The modified bradykinesia rating scale and Unified Parkinson's Disease Rating Scale demonstrated similar inter- and intrarater reliability. Raters placed greater weight on amplitude than on speed or rhythm when assigning a Unified Parkinson's Disease Rating Scale score. Modified bradykinesia rating scale scores for speed, amplitude, and rhythm correlated highly with quantitative kinematic variables. The modified bradykinesia rating scale separately captures bradykinesia components with interrater and intrarater reliability similar to that of the Unified Parkinson's Disease Rating Scale. Kinematic sensors can accurately quantify speed, amplitude, and rhythm to aid in the development and evaluation of novel therapies in Parkinson's disease.
authors.affiliation: Division of Movement Disorders, Cleveland Medical Devices, Inc., Cleveland, Ohio, USA.
authors.forename: Dustin A
authors.initials: DA
authors.lastname: Heldman
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Giuffrida
authors.forename: Robert
authors.initials: R
authors.lastname: Chen
authors.forename: Megan
authors.initials: M
authors.lastname: Payne
authors.forename: Filomena
authors.initials: F
authors.lastname: Mazzella
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Duker
authors.forename: Alok
authors.initials: A
authors.lastname: Sahay
authors.forename: Sang Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Fredy J
authors.initials: FJ
authors.lastname: Revilla
authors.forename: Alberto J
authors.initials: AJ
authors.lastname: Espay
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D004185:Disability Evaluation; D018737:Hand Strength; D006801:Humans; D018476:Hypokinesia / Q000175:diagnosis* / Q000209:etiology*; D008875:Middle Aged; D009039:Motion Perception; D009460:Neurologic Examination; D010300:Parkinson Disease / Q000150:complications*; D011597:Psychomotor Performance; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013223:Statistics as Topic; D014743:Videotape Recording