Robert Bonine is sure he made the right call five years ago to have a cancerous prostate removed.

Well, mostly sure.

"I don't have the sexual vigor that I had prior to the surgery," he lamented, "but hell, I'm 70."

Choosing surgery can be difficult, especially when medications or doing nothing can work just as well. But experts believe the decision can be easier if patients get clearer information about the risks and benefits.

Evidence came Thursday from the Dartmouth Atlas of Health Care, which found wide variations in surgery rates across Minnesota. The fact that elective back surgery is more common in St. Cloud than in St. Peter suggests that doctors' opinions play too big a role.

One solution used by the Stillwater Medical Group is "informed medical decision-making," which gives patients information and computer tools to weigh options before making choices with their doctors. "People are coming to a decision that they feel better about," said Dr. Larry Morrissey.

Whether broader use of the approach would reduce procedures -- and costs -- is unclear. One retired doctor told me that varying rates simply reflect doctors' varying comfort levels with different procedures.

The Dartmouth study, released Thursday, noted high orthopedic surgery rates in Stillwater. Morrissey stressed that the decision-making approach hasn't been used by the local orthopedic practice.

His group has focused on helping patients with decisions about breast and prostate cancers. Both can be problematic. Doctors differ not only on how to treat prostate cancer, but also on whether to screen older men for it at all. Screening rates varied widely among Minnesota communities, according to the data.

Prostate surgery improved Bonine's health and got rid of "the rat" of cancer. Had he been younger, he might have waited because of the surgery's impact on sex drive, he said.

Bonine said his doctor offered all options fairly. Still, the doctor's word choices probably had an influence on him.

"The teller of the options," he said, "is very powerful."