CallingSubProcedureWithParamByRef.vba

Option Explicit

Public Sub DoWork()
    Dim name As String
    name = "John"

    Call PrintName(name)
    Debug.Print "DoWork: " & name
End Sub

Private Sub PrintName(ByRef someName As String)
    someName = "Mr. " & someName
    Debug.Print "PrintName: " & someName
End Sub

' Output
' PrintName: Mr. John
' DoWork: Mr. John