The nncc package is an R package that provides a tool to implement nearest-neighbors matching for case-control data. Nearest-neighbors matching may improve confounding control if case-control data include too many exposures to control in a logistic regression model.

Project Admin

Beau B. Bruce, MD, PhD lue7@cdc.gov; CDC/NCEZID/DFWED/EDEB


# Install nncc from CRAN

# Or the development version from GitHub


If you have installed the nncc package, use vignette("nncc") or browseVignettes("nncc").

Otherwise, refer to https://CRAN.R-project.org/package=nncc/vignettes/nncc.html.

General disclaimer

This repository was created for use by CDC programs to collaborate on public health related projects in support of the CDC mission. GitHub is not hosted by the CDC, but is a third party website used by CDC and its partners to share information and collaborate on software. CDC use of GitHub does not imply an endorsement of any one particular service, product, or enterprise.

License Standard Notice

This repository bundles code licensed under the terms of the GNU General Public License v3.0, which can be found at https://www.gnu.org/licenses/gpl-3.0.en.html, and therefore is licensed under GPL v3.0 or later.

The source code in this repository is free: you can redistribute it and/or modify it under the terms of the GNU General Public License v3.0 or (at your option) any later version.

This source code in this repository is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

The source code forked from this project will inherit its license.

Privacy Standard Notice

This repository contains only non-sensitive, publicly available data and information. All material and community participation is covered by the Disclaimer and Code of Conduct. For more information about CDC’s privacy policy, please visit https://www.cdc.gov/other/privacy.html.

Contributing Standard Notice

Anyone is encouraged to contribute to the repository by forking and submitting a pull request. (If you are new to GitHub, you might start with a basic tutorial). By contributing to this project, you grant a world-wide, royalty-free, perpetual, irrevocable, non-exclusive, transferable license to all users under the terms of the Apache Software License v2 or later.

All comments, messages, pull requests, and other submissions received through CDC including this GitHub page may be subject to applicable federal law, including but not limited to the Federal Records Act, and may be archived. Learn more at https://www.cdc.gov/other/privacy.html.

Records Management Standard Notice

This repository is not a source of government records, but is a copy to increase collaboration and collaborative potential. All government records will be published through the CDC web site.

Additional Standard Notices

Please refer to CDC’s Template Repository for more information about contributing to this repository, public domain notices and disclaimers, and code of conduct.