> Yet 81 percent of the leading health economists agreed with the statement, “The primary reason for the increase in the health sector’s share of GDP over the past 30 years is technological change in medicine"

I've highlighted the role of technological change on my blog before, but technological change is a major proximate cause. The root cause is income growth. Countries are chasing these technological advancements in direct proportion to their income and the degree to which they can afford them (as prices fall, countries with lower real incomes are more able to afford technologies the US and other rich countries had long before, but the frontier has long since moved on....). If you throw year fixed-effects or a time trend into analysis the coefficient on time (a proxy for tech chg) is very modest and the income effects are virtually identical.