One big benefit: Like volume, specialization is simple and inexpensive to measure.
While the researchers used data from Medicare claims, hospitals have access to discharge data from all payers. So they can use their own health information technology systems to measure different surgeon's specialization and share it with referring physicians, Sahni says.
Relative Risk Reduction
The researchers looked at the impact of specialization on 30-day mortality rates for four cardiac procedures and four cancer operations. Measured by relative risk, the ratio of overall risk to the risk of mortality with a specialist, they found that the relative risk reduction from greater specialization ranged from 15% for coronary artery bypass grafting to 46% for valve replacement.
For the four cancer surgeries, the relative risk reduction in mortality ranged from 28% for lung resection to 48% for esophagectomy, removal of all or part of the esophagus.
For the six procedures with "statistically significant relative risk reduction," the absolute risk reduction—the difference between overall risk and risk of mortality with a specialist—ranged from 0.3% for carotid endarterectomy to 2.8% for abdominal aortic aneurysm repair.
The research may offer good news for smaller hospitals that have a hard time reaching volume thresholds.
"You have a critical access hospital in the mountains, and you're only going to see so many heart attacks," Sahni says. "With specialization, because it is independent of volume, it brings up this point: Maybe I just have my surgeons specialize instead of having a cardiovascular department with ten different surgeons. Each of them does whatever (cases) come in."
Since specialization is easy to measure and independent of volume, it could offer a way for smaller hospitals to improve mortality rates. It could also guide hiring decisions, Sahni said.
Tinker Ready is a contributing writer at HealthLeaders Media.