Valparam
You can use this function for Optiva Equations.
Purpose
LikeParam, ValParam returns the value of an object’s
         (formula, item) parameter, using the parameter’s unit of measure. In some cases, the
         modified state of the parameter returned by this function may lead to an incorrect value if
         called using the Param function on a parameter assigned to the lab as
         Equation Total. Therefore, ValParam is recommended for use with Equation
         Total Parameters.Syntax
Dim variable As String = valparam(parameter name)