Direct Primary Care Doctor Dr. Ingrid Liu is the owner and director of Progressive Health Primary Care, PLLC, an Oak Park-based Direct Primary Care practice. With an extensive medical background, Dr. Liu earned her undergraduate degree at the University of Illinois, Urbana Champaign, her osteopathic medical degree at the Chicago College of Osteopathic Medicine, and completed her residency at the West Suburban Hospital Family Medicine program in Oak Park. As a dedicated family