Dynamic article Content management

Hi,

So i'm building a publication template where there are articles filled through data acquired via a XML list. 

This works fine. But i want to make the articles available for only to those with the same interest category. I'm trying to establish this using this function:

<% if ( targetData.Interest.indexOf('PRODUCTA') > 0 ) { %>Insert content here<% } %>

When i test the if statement without using the publication template method it works.(So with just a normal delivery template) But when i try using it with the publication template i'm getting an error. I want to know if my method is possible before i spend hours searching for a way to fix the error. 

Thx!