Fig. 8

Authors keywords co-occurrence network Cluster 1 (5), [red]; Cluster 2 (4) [green], Cluster 3 (3) [blue], Cluster 4 (3) [lemon]. Note: The minimum number of co-occurrence was set at 5 and of the 428 keywords, 15 met the criteria. The bubble size indicates the most occurring keyword, while the colour refers to the clustering and line thickness the strength of the corresponding link