2D	Two Dimensions
3D	Three Dimensions
AdaBoost	Adaptive Boosting
ACC	Accuracy
ADL	Activity of Daily Living
AE	Autoencoder
AI	Artificial Intelligence
ALS	Amyotrophic Lateral Sclerosis
ANFIS	Adaptive Neuro-Fuzzy Inference System
ANN	Artificial neural Network
ANOVA	Analysis of Variance
AR	Autoregressive
ARMA	Autoregressive Moving Average
AU	Action Unit
AUC	Area Under the Curve
AUPR	Area under the Precision-Recall Curve
AUROC	Area Under the Receiver-Operating Characteristic Curve
Avg	Average
BDI	Beck Depression Inventory
BE	Backward Elimination
CAD	Computer-Aided Diagnosis
CART	Classification and Regression Tree
CFS	Correlation-based Feature Selection
CNN	Convolutional Neural Network
CT	Computed Tomography
CWT	Continuous Wavelet Transform
DA	Discriminant Analysis
DBN	Deep Belief Network
DCALSTM	Dual-modal Convolutional Neural Network + Attention Enhanced Long Short-Term Memory
DCNN	Dual-modal Convolutional Neural Network
DD	Other Movement Disorder
DESN	Deep Echo State Network
DFT	Discrete Fourier Transform
DL	Deep Learning
DNN	Deep Neural Network
DT	Decision Tree
DTW	Dynamic Time Warping
DWT	Discrete Wavelet Transform
ECG	Electrocardiography
EEG	Electroencephalography
EER	Equal Error Rate
ELM	Extreme Learning Machine
EMG	Electromyography
ESN	Echo State Network
ESS	Epworth Sleepiness Scale
ET	Essential Tremor
EWPT	Empirical Wavelet Packet Transform
EWT	Empirical Wavelet Transform
FA	Factor Analysis
FFT	Fast Fourier Transform
FIR	Finite Impulse Response
FLDA	Fisher Linear Discriminant Analysis
FNR	False Negative Rate
FoG	Freezing of Gait
FPR	False Positive Rate
FRP	Fuzzy Recurrent Plot
GBM	Gradient Boosting Machine
GD	Gradient Descent
GDM	Gradient Descent with Momentum
GM	Geometric Mean
GMM	Gaussian Mixture Model
GP	Gaussian Process
GRF	Ground Reaction Force
GRU	Gated Recurrent Unit
GS	Graph Sequence
H&Y	Hoehn and Yahr
HBNN	Hierarchical Bayesian Neural Network
HD	Huntington’s Disease
hHMM	Hierarchical Hidden Markov Model
HMCI	Healthy People with Mild Cognitive Impairment
HMM	Hidden Markov Model
HOA	Healthy Older Adult
HOG	Histogram of Oriented Gradients
IBk	Instance-Based with parameter k
ICC	Intraclass Correlation Coefficient
IIR	Infinite Impulse Response
IMU	Inertial Measurement Unit
IoT	Internet of Things
IPD	Idiopathic Parkinson’s Disease
JMIM	Joint Mutual Information Maximization
KELM	Kernel Extreme Learning Machine
KFD	Kernel Fisher Discriminant Analysis
kNN	k-Nearest Neighbors
LASSO	Least Absolute Shrinkage and Selection Operator
LDA	Linear Discriminant Analysis
LID	Levodopa-Induced Dyskinesia
LOSO	Leave One Subject Out
LR	Logistic Regression
LSTM	Long Short-Term Memory
MAE	Mean Absolute Error
MCC	Matthew’s Correlation Coefficient
MDS-UPDRS	Movement Disorder Society-Sponsored Revision of the Unified Parkinson’s Disease Rating Scale
MFCC	Mel-Frequency Cepstral Coefficient
ML	Machine Learning
MLP	Multilayer Perceptron
MMG	Mechanomyography
MML	Multi-source Multi-task Learning
MMTFL	Multiplicative Multi-Task Feature Learning
MoCA	Montreal Cognitive Assessment
MRI	Magnetic Resonance Imaging
mRMR	Maximum Relevance Minimum Redundancy
MS Kinect	Microsoft Kinect
mUPDRS	Motor subscale of the Unified Parkinson’s Disease Rating Scale
NB	Naïve Bayes
NN	Neural Network
OPF	Optimum Path Forest
PCA	Principal Component Analysis
PD	Parkinson’s Disease
PDD	Parkinson’s Disease Patients with Dementia
PDMCI	Parkinson’s Disease Patients with Mild Cognitive Impairment
PDNC	Parkinson’s Disease Patients with Normal Cognition
PET	Positron Emission Tomography
PKG	Personal KinetiGraph
PNN	Probabilistic Neural Network
PPV	Positive Predictive Value
PREC	Precision
PRISMA	Preferred Reporting Items for Systematic Reviews and Meta-Analyses
PSD	Power Spectral Density
PSG	Polysomnography
PSP	Progressive Supranuclear Palsy
Q-BTDNN	Q-Backpropagation for a Time Delay Neural Network
QDA	Quadratic Discriminant Analysis
RBD	Rapid Eye Movement Sleep Behavior Disorder
RBF	Radial Basis Function
REC	Recall
Res-Net	Residual Neural Network
RF	Random Forest
RGB	Red Green Blue
RGB-D	Red Green Blue-Depth
RMSE	Root Mean Square Error
RNN	Recurrent Neural Network
RUSBoost	Random UnderSampling Boosting
SBS	Sequential Backward Selection
SCG	Scaled Conjugate Gradient
SDE	Sparse Difference Embedding
SDH	Sum and Difference Histogram
sEMG	Surface-Electromyography
SENS	Sensitivity
SF-36	36-Item Short Form Survey
SFS	Sequential Forward Selection
SOM	Self-Organizing Map
SPDDS	Self-Assessment Parkinson’s Disease Disability Scale
SPEC	Specificity
STFT	Short-Time Fourier Transform
STL	Single Task Learning
SVM	Support Vector Machine
SVR	Support Vector Regression
TRIS	Treatment Response Index
TUG	Timed Up and Go
UDysRS	Unified Dyskinesia Rating Scale
UPDRS	Unified Parkinson’s Disease Rating Scale
VAE	Variational Autoencoder
VaP	Vascular Parkinsonism
VAS	Visual Analog Scale
XGBoost/XGB	Extreme Gradient Boosting