1. Division of Respiratory Therapy, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
2. Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
3. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
4. Department of Internal Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
5. Department of Respiratory Therapy, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan