/**
  *
  * @return
  */
 private static function clean_inconsistent_data($experiments)
 {
     if (count($experiments) == 0) {
         return;
     }
     $last_clean = get_option('nelioab_last_clean_of_inconsitent_data', false);
     if (NELIOAB_PLUGIN_VERSION == $last_clean) {
         return;
     }
     $ids = array();
     foreach ($experiments as $exp) {
         array_push($ids, $exp->get_id());
     }
     // Clean old widgets
     require_once NELIOAB_EXP_CONTROLLERS_DIR . '/widget-experiment-controller.php';
     NelioABWidgetExpAdminController::remove_alternatives_not_in($ids);
     update_option('nelioab_last_clean_of_inconsitent_data', NELIOAB_PLUGIN_VERSION);
 }