Table 1.
Characteristics of the participants.
Figure 1.
Classification of the severity of postural reflex disorder (PRD).
Figure 2.
A sample of the stride interval and the fluctuation relative to box size.
(A) PD patient with obvious postural reflex disorder (mH-Y score, 3; age 76 years; male). (B) PD patient with mild postural reflex disorder (mH-Y score, 2.5; age, 70 years; male). (C) PD patient with no postural reflex disorder (mH-Y score, 2; age, 76 years; male). (D) Healthy elderly person (age. 71 years; male).
Figure 3.
Classification according to the presence or absence of postural reflex disorder.
The no postural reflex disorder group (no-PRD) is indicated by blue points, and the postural reflex disorder group (PRD) is indicated by green points. The x-axis represents the CV, and the y-axis represents α. The data for the no-PRD group are distributed in a small CV region around 2%, whereas those for the PRD group are distributed in a large CV region roughly from 2.5% to 5%. The two groups have a wide and overlapping distribution of α. (A) Distribution of the original data. (B) Distribution of the normalized data. The solid line represents the boundary between the no-PRD group and the PRD group.
Figure 4.
Classification of obvious and mild postural reflex disorder.
The mild postural reflex disorder group (mild-PRD) is indicated by red points, and the obvious postural reflex disorder group (obvious-PRD) is indicated by light-green points. The x-axis represents the CV, and the y-axis represents α. (A) Distribution of the original data. (B) Distribution of the normalized data. The solid line represents the boundary between the mild-PRD and obvious-PRD groups.
Figure 5.
Concept of the evaluation platform.
The x-axis is related to the CV of the stride interval, and the y-axis is related to the α of the stride interval. PRD, postural reflex disorder.