Table 6. English and Chinese keywords clustering of DR research from 2015 to 2019.

English					Chinese
Cluster ID	Size	Silhouette	Mean (y)	Topic	Cluster ID	Size	Silhouette	Mean (y)	Topic
0	290	0.74	2015	Oxidative stress	0	74	0.648	2015	Diabetes mellitus
1	168	0.787	2015	Type 2 diabetes	1	73	0.616	2016	Calcium dobesilate
2	154	0.831	2015	Ranibizumab	2	69	0.623	2016	Vitrectomy
3	135	0.764	2015	Optical coherence tomography	3	42	0.749	2016	Vascular endothelial growth factor
4	88	0.8	2015	Blindness	4	42	0.764	2016	Nursing intervention
5	68	0.919	2016	Exudates	5	40	0.686	2015	Macular edema
					6	35	0.839	2016	Optical coherence
					7	27	0.85	2016	Fundus fluorescein angiography