           # it's relevant; it could be irrelevant based on preceding values, or
           # a calculation.
           if (next_question.bind?.calculate?) or not
-            XFormConstraintChecker.isRelevant( next_question, @queryStringToJSON( $( ".form" ).serialize()) )
+            XFormConstraintChecker.isRelevant next_question, @get_form_values()
 
               # If its a calculation, calculate it!
               $("#" + next_question.name).val _performCalcluate(next_question.bind.calculate)  if next_question.bind?.calculate?


        passes_question_constraints: ->
          question = document.flat_fields[@currentQuestionIndex]

          # Check if the question is required and whether or not a value is
          # present. If not, raise an alert.


          # Ensure that the question passes any constraints, if given. If
          # not, raise an alert.
          if not XFormConstraintChecker.passesConstraint question, answers
            alert "Answer doesn't pass constraint: #{child.bind['jr:constraintMsg'] or child.bind.constraint}"
            return false

          return true
