Table 1.

The NMBM of PD research of top 10 countries/regions.

Ranking	Country/region	Frequency	Centrality
1	USA	137	0.46
2	UK	40	0.19
3	China	39	0.02
4	Canada	38	0.09
5	Germany	37	0.17
6	Italy	32	0.07
7	Spain	23	0.15
8	Netherlands	16	0.05
9	Australia	14	0.27
10	South Korea	14	0.00

China = the People’s Republic of China, NMBM = neuroimaging biomarker, PD = Parkinson disease, UK = The United Kingdom of Great Britain and Northern Ireland, USA = United States of America.