I'm interested in replicating research that was conducted with an earlier version of an ICPSR study. Is it possible to get those data?

Yes, ICPSR can supply an earlier release version of a study unless that version is unavailable for confidentiality reasons or at the request of the principal investigator. Please send your request to ICPSR-help@umich.edu and include the ICPSR study title, study number, principal investigator, and the date and/or version of the data of interest. Data will be supplied electronically generally within a week or two of receipt of request.

How does ICPSR manage versioning?

  • What triggers a new edition or version of a study?
    • A change in any of the data and/or documentation files.
    • The addition or withdrawal of data and/or documentation files.
  • How and where is such a change to a study documented?
    • Version statement (For example, "Version V1"). 
    • The  DOI (For example, https://doi.org/10.3886/ICPSRXXXXX.v1). 
    • "Version(s)" tab on the study homepage (The "Version History" section provides a text description of what has changed, as well as a datestamp indicating when each change occurred). 
  • What happens to unchanged files (if changes don't apply to all files)?

ICPSR does not currently version at the individual file level, rather, our version statement references the collection as a whole. If only one file of a multiple file collection changes, the collection version changes.

  • Are previous editions/versions kept?

Yes, previous versions are kept through a back-up system and a searchable "browse archive" feature available to authorized ICPSR staff.

  • Are these made available to users?

Upon request only, previous versions can be made available to users.

  • Clarification on terminology, do we use "edition", "version", or other terms?
    • ICPSR uses "version" exclusively. Historically, ICPSR used three different terms: edition, version, and release, but these have all been rolled into the single term "version" and the notation "ICPSRXXXXX-v3".
    • What do we mean by "version"? A form or variant of the original ICPSR-archived data collection.