How to Access NACDA's Restricted Data

General Steps for Gaining Access to Restricted Data

  • Go to the study page
  • Select “Access Restricted Data”
  • Download the use agreement
  • Read the agreement
  • Most of the agreement fields can be completed on your computer, however, signatures must be original, therefore, print the agreement and sign it, then scan it back into a digital copy. (A lot of our agreements need to be updated to reflect that we do accept digital agreements, so while the signature must be original, we accept scanned versions of the agreement so that users may email them to us.)
  • Some studies, such as NSHAP, require an IRB or protection plan, the terms are all outlined in the agreement; users should read the agreement carefully to understand all of the necessary steps for completing the agreement. If the agreement requires an IRB and other materials, users should obtain and prepare to send those materials along with the agreement.
  • It’s not required, however, it does help to name your file to identify your name, the study, and the month and year - for example “Smith_Joan_NSHAPwave1_may2019.pdf”.
  • If the agreement does not require an IRB or additional steps, then next you would email your completed agreement.
  • Once we receive your agreement, we will review it and let you know if we have questions.
  • If everything looks good, we will ask our data services specialist to send you an encrypted link to obtain the files. There are times we may be available to send the encrypted link within one business day, although sometimes it may take a few days depending on schedules and other constraints.
  • Keep an eye on your email from a “” address, once we send you the encrypted link, it may expire after several days have passed.
  • Download the file(s) (.exe)
  • For MAC users - you will need to download a free software application called Stuffit! Expander from the Apple Store in order to access the files. It's more compatible with the compression algorithms we use.
  • After you download the files, request the password via email from the data services specialist (replying directly is preferred), please keep in mind that the link and password are time sensitive.
  • After you receive the password, complete your download process.
  • This process can take 2 weeks, as there are people behind these steps and we may not receive your request right away. In general, it takes less than 2 weeks.
  • Use the data!

Send us your publication citation so we can link it to the studies you used.