public function renderRespondent($id_respondent)
 {
     if ($id_respondent === null) {
         $this->redirect("Results:");
     }
     $respondent = $this->respondent_service->getResultsRespondentDetail($id_respondent);
     if (!$respondent) {
         $this->redirect("Results:");
     }
     $this->template->respondent = $respondent;
     $this->template->categories = $this->entity_category_service->getResultsRespondentCategory(new RespondentCategory(array(RespondentCategory::ID_RESPONDENT => $id_respondent)));
 }