As always your analysis is very thorough. My question would be what the cause is behind the difference. Maybe we should include in the analysis the economic context and find out the differences in how transactions occur in healthcare?
Healthfinancing systems, or the lack thereof, the investments in healthcare, consumption indicators, medical expense inflation, government expenditure in relation to ODA, medical tourism expenditure can give a view on how a health market is performing on an economic basis.
Example: if investments are low or decreasing, it gives a view on how risk factors develop?
Hope this is a valuable amendment and look forward to your future research!