Emily Y. Chew, M.D.

NIH Distinguished Investigator

DECA - Clinical Trials Branch


Building 10-CRC, Room 3-2531,
10 Center Drive,
Bethesda, MD-20892



Research Topics

The mission of the Clinical Trials Branch of the Division of Epidemiology and Clinical Applications is to conduct the highest quality clinical research. As previously stated in the overview of the division: "It is the Division's mission to plan, develop, and conduct human population studies concerned with the cause, prevention, and treatment of eye disease and vision disorders, with emphasis on major causes of blindness. This includes studies of incidence and prevalence in defined populations, prospective and retrospective studies of risk factors, natural history studies, clinical trials, genetic studies, and studies to evaluate diagnostic procedures." The goals of the Clinical Trials Branch are to evaluate potential therapies through translational studies including phase I/II studies and other clinical research. We primarily design and conduct phase III randomized controlled clinical trials to evaluate therapies to improve the vision of the American people. We also assist both intramural and extramural communities in the development and conduct of clinical research.The Clinical Trials Branch focus on the leading causes of blindness, age-related macular degeneration, diabetic retinopathy and cataract.


Emily Chew is the Director of the Division of Epidemiology and Clinical Applications (DECA), at the National Eye Institute, the National Institutes of Health in Bethesda, Maryland. She is also the Chief of the Clinical Trials Branch in the division. Emily received her medical degree and her ophthalmology training at the University of Toronto, Canada. She completed her fellowship in medical retina at the Wilmer Eye Institute, the Johns Hopkins Medical Institutes and the University of Nijmegen, the Netherlands. Her research interest includes phase I/II clinical trials and epidemiologic studies in retinovascular diseases such as age-related macular degeneration, diabetic retinopathy, and other ocular diseases. She has worked extensively in large multi-centered trials headed by the staff from her division, including the Early Treatment Diabetic Retinopathy Study (ETDRS), the Age-Related Eye Disease Study (AREDS) and the Age-Related Eye Disease Study 2 (AREDS2), which she chairs. She works on other clinical trials in collaboration with other institutes within NIH such as the Actions to Control Cardiovascular Risk in Diabetes (ACCORD) Trial and she chairs the ACCORD Eye Study. She directs the clinical portion of the international study, Macular Telangiectasia Project.

Selected Publications

  1. Klein RJ, Zeiss C, Chew EY, Tsai JY, Sackler RS, Haynes C, Henning AK, SanGiovanni JP, Mane SM, Mayne ST, Bracken MB, Ferris FL, Ott J, Barnstable C, Hoh J. Complement factor H polymorphism in age-related macular degeneration. Science. 2005;308(5720):385-9.
  2. Fleckenstein M, Keenan TDL, Guymer RH, Chakravarthy U, Schmitz-Valckenberg S, Klaver CC, Wong WT, Chew EY. Age-related macular degeneration. Nat Rev Dis Primers. 2021;7(1):31.
  3. ACCORD Study Group, ACCORD Eye Study Group, Chew EY, Ambrosius WT, Davis MD, Danis RP, Gangaputra S, Greven CM, Hubbard L, Esser BA, Lovato JF, Perdue LH, Goff DC Jr, Cushman WC, Ginsberg HN, Elam MB, Genuth S, Gerstein HC, Schubart U, Fine LJ. Effects of medical therapies on retinopathy progression in type 2 diabetes. N Engl J Med. 2010;363(3):233-44.
  4. Chew EY, Clemons TE, Agrón E, Launer LJ, Grodstein F, Bernstein PS, Age-Related Eye Disease Study 2 (AREDS2) Research Group. Effect of Omega-3 Fatty Acids, Lutein/Zeaxanthin, or Other Nutrient Supplementation on Cognitive Function: The AREDS2 Randomized Clinical Trial. JAMA. 2015;314(8):791-801.

Related Scientific Focus Areas

This page was last updated on Friday, November 17, 2023