Background In neuroscience clinical research studies, much time and effort are devoted to deciding what data to collect and developing data collection forms and data management systems to capture the data. Many investigators receiving funding from National Institute of Neurological Disorders and Stroke (NINDS), the National Institutes of Health (NIH), are required to share their data once their studies are complete, but the multitude of data definitions and formats make it extremely difficult to aggregate data or perform meta-analyses across studies. Purpose In an effort to assist investigators and accelerate data sharing in neuroscience clinical research, the NINDS has embarked upon the Common Data Element (CDE) Project. The data standards developed through the NINDS CDE Project enable clinical investigators to systematically collect data and should facilitate study start-up and data aggregation across the research community. Methods The NINDS CDE Team has taken a systematic, iterative approach to develop the critical core and the disease-specific CDEs. The CDE development process provides a mechanism for community involvement and buy-in, offers a structure for decision making, and includes a technical support team. Results Upon conclusion of the development process, the CDEs and accompanying tools are available on the Project Web site – http://www.commondataelements.ninds.nih.gov/ . The Web site currently includes the critical core (aka general) CDEs that are applicable to all clinical research studies regardless of therapeutic area as well as several disease-specific CDEs. Additional disease-specific CDEs will be added to the Web site once they are developed and vetted over the next 12 months. Limitations The CDEs will continue to evolve and will improve only if clinical researchers use and offer feedback about their experience with them. Thus, the NINDS program staff strongly encourages its clinical research grantees to use the CDEs and is expanding its efforts to educate the neuroscience research community about the CDEs and to train research teams to incorporate them into their studies. Conclusions Version 1.0 of a set of CDEs has been published, but publication is not the end of the development process. All CDEs will be evaluated and revised at least annually to ensure that they reflect current clinical research practices in neuroscience.

National Institute of Neurological Disorders and Stroke Common Data Element Project – approach and methods