Some key papers have sought to address these empirical challenges.
Gruber et al.(2005) use the introduction of pre-tax payment
of premiums for postal workers (and, later, all federal workers) as a
source of plausibly exogenous variation in effective premium price
and estimate elasticities close to zero. Cutler and Reber (1998) find
much larger price elasticities (near −1.0) using a change in Harvard
University’s employee health plan premiums. AsAbraham and
Feldman (2010) note, it is interesting that the two studies exploiting
natural experiments to estimate the demand for employer
insurance yield such markedly different results, but then the samples
used—postal workers and Harvard employees—might be very
different from each other.