Comparing the prices of medicines across borders is an intellectual challenge for academics, a profitable business for consultants and a difficult issue for pharmaceuticals companies. But there is growing appetite for the practice among healthcare systems in richer and poorer countries alike.

Recent efforts by the Chinese government to step up scrutiny of drug prices reflects spiralling domestic healthcare costs as public and private demand for improved health grows, against a background of growing tensions over the industry’s past commercial approaches.

As healthcare spending comes under increasing pressure in the drug industry’s large traditional markets in North America, western Europe and Japan, fast growing countries like China have become ever more important source of revenues.