The security of our participants' personal information is our highest priority. We take a variety of steps to keep all information collected during the course of the study confidential. First, the Harvard-affiliated Partners Human Research Committee reviews all of our procedures to ensure compliance with regulations for the storage and sharing of data, and to approve all new research projects.

We will never give participants' name, address, or any other personally identifiable information to anyone not part of the conduct of the study. We have been issued a Certificate of Confidentiality by the federal government, which allows us to refuse to disclose personally identifiable information to anyone.

NHS data are never stored on portable devices like phones, laptops, or tablets. The data files we use for analysis contain only study ID numbers. All names, addresses, and social security numbers are stored on a separate, highly secure computer system that only a small, select group of senior staff can access. As a result, even our investigators do not know the identities of participants in any given set of data.

For maximum security, we use state-of-the-art digital protection tools to prevent possible intrusions, and our internal network is monitored constantly. For our online questionnaires, our website uses encrypted data transmission to ensure that responses can't be intercepted as they are sent to our computer servers.

Confidentiality is critical to the Nurses' Health Studies, and we work hard to earn—and maintain—participants' trust.