The volume-outcome relationship: from Luft to Leapfrog.

Area of Science:

• Health Services Research
• Surgical Outcomes
• Healthcare Quality Improvement

Background:

• A volume-outcome relationship is documented for complex medical and surgical care.
• Many existing studies are limited by data sources, risk adjustment, and statistical methods.
• Volume-based referral strategies are proposed for healthcare quality improvement.

Purpose of the Study:

• To evaluate the utility of volume-based referral strategies in healthcare.
• To identify specific procedures and patient subgroups where volume standards are most appropriate.
• To advocate for the use of risk-adjusted outcome data over volume standards.

Main Methods:

• Review of existing literature on volume-outcome relationships in healthcare.
• Analysis of the appropriateness of volume-based referral strategies for different procedures.
• Examination of the Leapfrog Group's minimum volume requirement for coronary artery bypass grafting.

Main Results:

• Volume-outcome relationships exist for complex procedures like esophagectomy and pancreatectomy.
• Volume standards are most effective for procedures with high outcome variability and high-risk patient subgroups.
• The basis for specific volume recommendations, such as the Leapfrog Group's 500-procedure minimum for CABG, warrants reevaluation.

Conclusions:

• Volume-based referral strategies can be a useful tool for healthcare quality improvement when outcome data is limited.
• Risk-adjusted outcome data should supplement or replace volume standards whenever feasible.
• Continuous quality improvement programs should focus on emulating processes of high-volume, high-quality providers.