A century ago, many doctors in rural areas of the United States were paid on a barter system — literally exchanging meat and vegetables from farmers for medical services. That system changed in the 20th century, of course, with the rise of the health-insurance industry.

Now, in a remarkable sign of the deterioration of that 20th century institution, doctors are increasingly taking their fees in cash — a phenomenon that is producing surprising results:

[Instead] of losing patients because they no longer take insurance, the recent job market has actually boosted the patient base for some cash-only doctors. Patients who have lost jobs — and the health insurance that went with those jobs — seek out cash-only practices, which typically charge less.

Even patients who are still employed have seen deductibles soar, so that some insured patients essentially pay out of pocket for routine care. They, too, have been seeking out cash-only practices.

Will the current economic climate continue to increase the number of physician who go cash-only?

Seven out of 10 respondents to a MedPage Today online spotcheck think so.

And so do a handful of new services — such as SimpleCare and PriceDoc — aimed at bringing cash-only patients together with cash-only doctors.

Statistics on the number of cash-only physicians are hard to come by, but, according to the CDC, in 2005-06, 11 percent of physicians had no managed care contracts.

These cash-only physicians are earning less than they used to, but that’s a trade-off that few regret.

Cash-only practices have less overhead, particularly because there are no billing (or collection) fees since the payment is collected at the time of service. These physicians also tend to have lighter case loads, which can help them build strong partnerships with their patients.