Actually, this index was not created by the Institute, but by researchers at the Economist Intelligence Unit. The researchers used available data and developed a series of indicators to rank countries in terms of palliative care. They looked at whether countries had a national policy framework on palliative care. When they created the index in 2015, there were none.
They also looked at such factors as government investment in health care, resources for targeted training in palliative care, the availability of subsidies to support families and reduce the burden on informal caregivers, as well as access to opioid analgesics.
Various measures were available at the time. Since 2015, the situation has changed somewhat. As regards international comparison, I know that the OECD is interested in it. All developed countries have aging populations and palliative care is becoming an increasingly important issue.
I think there will be work to do in the future to improve international comparisons in palliative care.