A study comparing prices for hospital stays, physician office visits, drugs and other medical procedures in developed countries shows U.S. prices among the most expensive. The International Federation of Health Plans, a London-based network of 100 insurance companies in 30 developed nations, annually looks at prices, and last week published its 2011 Comparative Price Report on medical and hospital fees by country. Among the results: Cost per day for hospital charges averaged $3,949 in the U.S., followed by Chile at $1,552. The average hospital cost for a U.S. patient’s total stay was $15,734; Germany was next at $5,004.