1. Department of Pain Management, The Third Hospital Affiliated to Hebei Medical University, Shijiazhuang, Hebei, China (mainland)
2. Department of Laboratory, The First Hospital of Shijiazhuang, Shijiazhuang, Hebei, China (mainland)
3. Department of Palliative Care, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China (mainland)