Medical One Clinic Address 29 NW 1st Lane Lamar, MO 64759 location Get Directions Phone: 417-681-5266 Hours 7 a.m.-7 p.m., Monday through Friday About The Medical One Clinic at Cox Barton County Hospital has a team of health care professionals to care for you and your entire family. Our services include management of chronic health conditions, women's health care, diabetic care, orthopedic services, preventive care and more.