Visit this page regularly for updates on data resources and archives.

New Add Health Data Release The following data are now available to Add Health contract researchers. Current Add Health investigators can log in to the CPC Data Portal and use the “Request More Data” button to order this dataset. For more information on the CPC Data Portal, please visit the Frequently Asked Questions page

All Coded Causes of Death File, Including Entity-Axis Codes, 2021 This file contains all underlying cause of death and entity-axis codes appearing in the National Death Index (NDI) source file through 2021. Functioning as dummy variables, zero represents the absence of a code on the decedent’s death certificate, while one denotes the presence of one. N=647

All Coded Causes of Death File, Including Record-Axis Codes, 2021 This file contains all underlying cause of death and record-axis codes appearing in the National Death Index (NDI) source file through 2021. Functioning as dummy variables, zero represents the absence of a code on the decedent’s death certificate, while one denotes the presence of one. N=647

Individual Vital Status and Underlying Cause of Death File, 2021 This file contains one record for each of the 20,745 Add Health sample members from Wave I. It provides the vital status of each sample member through 2021 as well as the National Death Index-provided underlying cause of death code in ICD-10 format for each decedent. The month and year of the most recent Add Health interview are provided for living sample members, while the month and year of death are provided for decedents. N=20,745

Ordered Cause of Death File, 2021 This file contains entity- and record-axis codes reported by the National Death Index (NDI) for each decedent in the Add Health sample through 2021. The file is arranged hierarchically, by axis code; therefore, each decedent may have multiple records depending on the maximum number of entity- and record-axis codes recorded by NDI. The sequence of the decedent’s records reflects the order in which the entity- and record-axis codes were reported in the NDI record. N=2,123

Add Health – The National Longitudinal Study of Adolescent to Adult Health In collaboration with the UNC Chief Information Officer and the Research Computing Unit at the University of North Carolina – Chapel Hill, Add Health is making the UNC Secure Research Workspace (UNC SRW) available for restricted-use contract researchers to analyze Add Health data in UNC’s enterprise secure data enclave free of charge. This is a major upgrade to the way Add Health is disseminating restricted-use data and we think will be very helpful for users of restricted-use Add Health data all over the world. In a nutshell, this means we will phase out “pushing data out” to the user community. Instead, contract users will use Add Health data by logging in to the SRW at UNC. This should make using Add Health data easier for the user community. Moreover, it will help keep Add Health data more secure in our efforts to maintain the strict confidentiality of our participants. Use of the UNC SRW is free. More information and how to access the SRW can be found on our website. We will continue to put tremendous effort into collecting and disseminating great data for the scientific community. Please contact us at if you have questions or concerns regarding our transition to the UNC SRW.

ICPSR. ICPSR at University of Michigan maintains a data archive of more than 250,000 files of research in the social and behavioral sciences. It hosts 21 specialized collections of data in education, aging, criminal justice, substance abuse, terrorism, and other fields. Access the site here.

National Couples’ Health and Time Study Data (NCHAT; N = 3,642 main respondents and N = 1,515 partner/spouses) is the first population-based study of couples that contains large representative samples of individuals who are racial and ethnic diverse and sexual and gender diverse. NCHAT main respondent survey data, funded by NICHD, are now publicly available from the Data Sharing for Demographic Research at ICPSR. Users can also apply to use the restricted data, for free, through DSDR on a virtual data enclave. There is a free virtual training workshop on August 18th, registration details can be found here. Users can learn more about the data in this working paper. NCHAT was collected during the COVID-19 pandemic and included adults in the US who ranged in age from 20-60 years old, who were married or cohabiting, and who were able to read English or Spanish. NCHAT includes dyadic survey, time diary, experience sampling methods, and geospatial data. NCHAT is uniquely suited to address COVID, stress, family functioning, and physical and mental health and includes an abundance of contextual and acute measures of race and racism, sexism, and cis-heterosexism. NCHAT includes a full household roster and marital and cohabitation histories. The gender neutral surveys are available in English and Spanish on the NCHAT website.

National Voter File. BU has has acquired a three-year subscription to a national voter file for the United States. These data, which are from the commercial data vendor L2, includes records on over 200 million voters plus 2.3 billion voter history records. To learn more, and access data, click here.  Questions should be directed to Maxwell Palmer (

U.S. Census Bureau Small Area Income and Poverty Estimates 2019 School District Profile Interactive Tool. Released in October 2021, this data visualization dashboard provides information on every one of the nation’s more than 13,000 school districts as defined in the 2020 School District Review Program. Access the site here. 

The National Historical Geographic Information System (NHGIS) provides easy access to summary tables and time series of population, housing, agriculture, and economic data, along with GIS-compatible boundary files, for years from 1790 through the present and for all levels of U.S. census geography, including states, counties, tracts, and blocks. Over 1,300 new tables are now available for geographic areas with 65,000 or more residents. NHGIS has added the 2021 1-Year Summary File from the American Community Survey (ACS) and has also completed over 1,400 updates in the “context fields” for selected summary datasets, including area measures, geographic coordinates, data suppression flags, and geographic class codes (e.g., incorporated vs. unincorporated places). Read more.