Nurses' Health Study

The Nurses' Health Study, established in 1976 by Dr. Frank Speizer, and the Nurses' Health Study II, established in 1989 by Dr. Walter Willett, were long-term epidemiological studies conducted on women's health. The study followed 121,700 female registered nurses since 1976 and 116,000 female nurses since 1989 to assess risk factors for cancer and cardiovascular disease. The studies are among the largest investigations into risk factors for major chronic diseases in women ever conducted. The studies include clinicians, epidemiologists, and statisticians at the Channing Laboratory. Participating organizations from the Massachusetts medical community include the Harvard Medical School, Harvard School of Public Health, and several Harvard-affiliated hospitals, including Brigham and Women's Hospital, Dana–Farber Cancer Institute, Children's Hospital Boston, and Beth Israel Deaconess Medical Center.

The study is recruiting a new cohort of 100,000 licensed practical nurses (LPNs) and registered nurses (RNs) (or those studying to become one) aged 20–46, for a cohort called the Nurses' Health Study 3 (NHS3). NHS3 is completely online, using social media for recruitment. Notably, unlike prior iterations of the survey, NHS3 is not restricted solely to female participants.

A cohort of nurses aged 30 to 63 were initially surveyed in 1976 and biennially thereafter. A second cohort of nurses were enrolled in 1989.

Over time additional questions have been added, most notably the dietary assessment added in 1980. Deaths, usually reported by kin or by postal authorities, were followed up. Where possible and permitted, in cases suggestive of cardiovascular disease/coronary heart disease the followup went beyond death certificates to gather available documentation from autopsy reports and other records. Mortality followup is better than 98 percent.

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