Studying just the health of, say, a country’s economy or political system, is like studying just the health of a person’s finger. In order to gain the knowledge to manage the global political system effectively, mankind needs a scientific field (or, more precisely, perhaps a subfield of political science) devoted to diagnosing the health of the global political system. All the methods discussed in this site are relevant diagnostic tools.
The Global Political Health Overview page provides an overview of how one might approach the definition of such a field of study. Here is the study on which the overview is based.