The proposition that stock traders are nervous these days would elicit little dissent, but stock analysts are clarifying their interpretations last week of an impending set of Medicare demonstration programs geared toward reviewing hospital claims before those claims are paid. At least one stock analyst, Larry Biegelsen of Wells Fargo (New York) has communicated that he sees a Dec. 2 sell-off of med-tech stocks as "an overreaction" to the news.