Fig. 5
From: Health policy and systems research collaboration pathways: lessons from a network science analysis
Successive magnification of a segment of the HPSR co-authorship network from 1990 to 2015 (starting from top right panel, to left, to bottom right panel) reveals a more intricate collaborative relationship between authors from different economic classifications. While in the previous cumulative intervals, authors from high-income countries used to play a dominant role in the overall connectivity of the network, the 1990–2015 cumulative interval shows that upper-middle-income countries (UpperMICs) are catching up in establishing their influence on the network. Orange colour indicates low-income countries (LICs), green for lower middle-income countries (LowerMICs), pink for UpperMICs and blue for high-income countries (HICs)