IIF Date Comparision with MDX

Hello,

I'm using the below to compare the date and hopind it to return the True,false condition from IIf. But none of the below are working for me, can someone please help me understand what is that i'm doing wrong.

any suggestion would be of great help! Thanks

--iif( (CDATE([Dim Plan Year].[Plan Year].CURRENTMEMBER) = CDATE([Dim Plan Year].[Plan Year].&[2013])), true condition, false condition)

--iif( (CDATE([Dim Plan Year].[Plan Year].CURRENTMEMBER) >= 2013) , true condition, false condition)

--iif( ([Dim Plan Year].[Plan Year].MEMBERVALUE >=2013 ) , true condition, false condition)

--iif( ([Dim Plan Year].[Plan Year].CURRENTMEMBER.NAME >=2013 ) , true condition, false condition)

--iif( ([Dim Plan Year].[Plan Year].CURRENTMEMBER.MEMBER_CAPTION >= 2013 ) , true condition, false condition)

--iif( (STRTOVALUE([Dim Plan Year].[Plan Year].CURRENTMEMBER.MEMBER_CAPTION) >= 2013 ) , true condition, false condition)