sql scripts - Set SQL alias value -

is there way set value of alias isapprover checking on column or e.g. (if control.approverid or process.tapprover has value set alias true value)

here 2 columns:

cast(case          when max(isnull(process.tapprover,0)) = :memberid             1             else 0       end bit) isapprover,  cast(case          when max(isnull(control.approverid,0)) = :memberid             1             else 0       end bit) isapprover,