Call rendered data field in CreatedRow

Hi,
i would like to check in CreatedRow if a rendered field is negative number or not so that i color red the font or the cell background.
How to refer to the data:null field ?
eg.

    if(data.field1 > 0  ) { // works if field1 was not rendered
    $(row).find('td:eq(11)').css('color', 'green');
    }