  A country's research success can be assessed from the power law function that
links country and world rank numbers when publications are ordered by their
number of citations; a similar function describes the distribution of country
papers in world percentiles. These functions allow calculating the ep index and
the probability of publishing highly cited papers, which measure the efficiency
of the research system and the ability of achieving important discoveries or
scientific breakthroughs, respectively. The aim of this paper was to use these
metrics and other parameters derived from the percentile-based power law
function to investigate research success in the USA, the EU, and other
countries in hot medical, biochemical, and biotechnological topics. The results
show that, in the investigated fields, the USA is scientifically ahead of all
countries and that its research is likely to produce approximately 80% of the
important global breakthroughs in the research topics investigated in this
study. EU research has maintained a constant weak position with reference to
USA research over the last 30 years.
