protected function _checkFilterUsed($filter)
    {
        $filter = parent::_checkFilterUsed($filter);

        if (isset($filter['gr2o_id_organization'])) {
            // Check for option to check for any organization
            if (true === $filter['gr2o_id_organization']) {
                unset($filter['gr2o_id_organization']);
            }
        } else {
            // Add the correct filter
            if ($this->isMultiOrganization() && !isset($filter['gr2o_patient_nr'])) {
                $allowed = $this->currentUser->getAllowedOrganizations();

                // If we are not looking for a specific patient, we can look at all patients
                $filter['gr2o_id_organization'] = array_keys($allowed);
            } else {
                // Otherwise, we can only see in our current organization
                $filter['gr2o_id_organization'] = $this->getCurrentOrganization();
            }
        }

        if (self::SSN_HASH === $this->hashSsn) {
            // Make sure a search for a SSN is hashed when needed.
            array_walk_recursive($filter, array($this, 'applyHash'));
        }

        return $filter;
    }