How to hide an entire tab based off of a drop down field selection??

I am trying to hid an entire tab if a field above is Yes or Blank.  Below is my script, but I keep getting an error that says, "ReferenceError: 'CombineExtractWithExistingExtractOnload' is undefined
   at eval code (eval code:1:1)"

function ProposedClaimsExtractSetupOnLoad()
 {
  var CombineExtractWithExistingExtract = Xrm.Page.getAttribute("nhs_combineextractwexistingextract_y_n_tbd").getSelectedOption();
  if (CombineExtractWithExistingExtract == null || CombineExtractWithExistingExtract =='undefined' || CombineExtractWithExistingExtract =='' || CombineExtractWithExistingExtract =='Yes' )
   {
    Xrm.Page.ui.tabs.get("tab_ProposedClaimsExtractSetup").setVisible(false);
   }
 }  

Any help is appreciated, thank you.