Her historical scholarship appears in her book Needles, Herbs, Gods, and Ghosts: China, Healing, and the West to 1848 (Harvard University Press, 2005).
This anthropologically influenced cultural history examines how understandings of medicine, religion, race, and the body informed how Westerners in both Europe and later the U.S. understood and responded to the Chinese and their healing traditions from the thirteenth century through 1848.
She is currently writing a book on the cultural and social history of Chinese medicine and healing traditions in the United States, beginning in 1849 and continuing up through the present.
As part of this project, Barnes has conducted fieldwork funded by the National Library of Medicine, and gathered hundreds of oral histories in regions throughout the United States, while also building an archive of related source materials.
A second major scholarly area to which Barnes has contributed is the interdisciplinary and cross-cultural study of relationships between religious, medical, and therapeutic traditions.