Channing Division of Network Medicine Cohorts

Nurses' Health Study (PI: M. Stampfer) began in 1976 with the enrollment of 121,000 female nurses, ages 30-55

Health Professionals Follow-up Study (PI: W. Willett) based primarily at Harvard T.H. Chan School of Public Health, began in 1986, and enrolled 52,000 male health professionals, ages 40-75

Nurses' Health Study II (PIs: W. Willett and H. Eliassen) joint study between Channing Division of Network Medicine and Harvard T.H. Chan School of Public Health, began in 1989 with the enrollment of 117,000 nurses, ages 25-42

These three cohorts are followed through biennial questionnaires, which gather repeated detailed information about diet, activity, other lifestyle variables, and health, including medications. These assessments have been carefully validated and calibrated. We also collect information on quality of life, mental health, and social factors. Additionally, extensive data are collected on the environment, such as air pollution.

Many disease outcomes (cancers, stroke, coronary disease, etc.) are documented through medical records. Other important outcomes are confirmed through supplementary questionnaires (e.g., diabetes, fractures, etc.) or through testing (cognitive function).

About a third of each cohort provided blood samples (for plasma, DNA, red cells), with a repeated collection in a subset of the Nurses. In addition, we collected salivary DNA on thousands of participants who did not provide blood, and we collect tumor tissue for many of the cancers. A stool collection is ongoing in NHS II.

All three cohorts continue to be followed, with follow-up rates of about 90%.

Growing Up Today Study (GUTS) established in 1996, follows over 26,000 offspring of women in the Nurses'; Health Study II. In 1996, 16,882 children were enrolled in GUTS I, and 10,923 children were enrolled in GUTS II in 2004.

Nurses’ Health Study 3 (joint between Channing Division of Network Medicine and Harvard T.H. Chan School of Public Health) began in 2010 under the direction of Dr. Walter Willett, Janet Rich-Edwards, Stacey Missmer, and Jorge Chavarro. For the first time ever, the study is entirely web-based. Participants include female and male LPN/Licensed Vocational Nurses (LVNs) and RNs, as well as nursing students, ages 20-46. NHS3 is also open to nurses in Canada.