Costs vs. Benefits - NYTimes.com Re "When Robotic Surgery Leaves Just a Scratch" (Novelties, Nov. 18), which described how robotic systems could perform single-incision surgery: While scientific advances may soon leave surgery patients with "just a scratch," what financial wounds may be added to our nation's struggling health care system? The aesthetic and functional appeal of single-incision operations and similar advanced technologies should be balanced against the growing necessity to judge novel interventions not only by their cost effectiveness but also by the opportunity costs associated with their potential widespread adoption. In an era of ever-tightening fiscal budgets, dismal access to primary care, and unenviable population health, how much is a single, one-inch scar really worth? Jason P. Lott, M.D. New Haven, Nov. 19 The writer is a post-doctoral fellow in the Robert Wood Johnson Foundation Clinical Scholars Program at the Yale University School of Medicine. Letters for Sunday Business may be sent to sunbiz@nytimes.com