Table 1: Year of scope of practice reform.

AlaskaPrior to 1989
ArizonaPrior to 1989
IdahoPrior to 1989
OregonPrior to 1989
UtahPrior to 1989
WashingtonPrior to 1989
DC1991
Montana1991
Rhode Island1991
Iowa1992
New Hampshire1992
Wyoming1992
Maine1993
New Mexico1993
Colorado*2009
Hawaii*2009
Maryland*2010

* Not included in analysis.