public function qualifies_for_regrading() {
        if (empty($this->id)) {
            debugging("Can not regrade non existing category");
            return false;
        }

        $db_item = grade_category::fetch(array('id'=>$this->id));

        $aggregationdiff = $db_item->aggregation         != $this->aggregation;
        $keephighdiff    = $db_item->keephigh            != $this->keephigh;
        $droplowdiff     = $db_item->droplow             != $this->droplow;
        $aggonlygrddiff  = $db_item->aggregateonlygraded != $this->aggregateonlygraded;
        $aggoutcomesdiff = $db_item->aggregateoutcomes   != $this->aggregateoutcomes;

        return ($aggregationdiff || $keephighdiff || $droplowdiff || $aggonlygrddiff || $aggoutcomesdiff);
    }