In 2007, Chang and coauthors retracted five previously published papers describing the structures of three multidrug transporter proteins after another research group published a widely differing structure, which led to the discovery of a critical bug in the Chang group's custom software tools. Since that time, however, Chang has published other papers in the field of structural biology, and has been awarded a EUREKA grant, "for exceptionally innovative research projects that could have an extraordinarily significant impact on many areas of science," from the National Institutes of Health.