To quote Brian Klepper,"Medicare’s payment system, which is the basis for most commercial payment as well, favors specialists in two ways. It pays them a higher rate for their time (implying that what they do is more difficult and more valuable), and it allows them to earn money through procedures that are unavailable in primary care."

And,

"[This] post reminded me of Jared Diamond’s great, cautionary book, Collapse. Diamond describes society after society in which leaders knowingly made decisions that undermined their survival. But they couldn’t course correct because the decision-makers were benefiting from the current circumstances. I wonder whether we’ll be able to avoid that fate."

"Bad Medicine: How the AMA Has Undermined Primary Care"

See, also, Bodemheimer T, Berenson RA and Rudolf, P. "The Primary Care-Specialty Income Gap: Why It Matters." [PDF]

"Under the RBRVS system, the 2005 Medicare fee for a typical 25- to 30-minute office visit to a primary care physician in Chicago was $89.64 for a patient with a complex medical condition…. The 2005 Medicare fee was $226.63 for a gastroenterologist in the outpatient department of a Chicago hospital performing a colonoscopy … which is of similar duration to the office visit. Colonoscopy performed in a private office in Chicago, which differs from the hospital setting because the gastroenterologist pays for equipment and nursing time, would cost $422.90…"