Data with Confidential Content

Sharing Data

All fields directly identifying research subjects must be removed prior to deposit. If the data contains direct identifiers and/or contact information (i.e., a roster file with names, addresses, etc.), these should not be shared. Indirect identifiers may remain in the data if needed to reproduce original findings or if removing them would significantly degrade the dataset’s value.

NACJD archiving activities to process data for release include conducting a confidentiality review and using information provided by the depositor to create data files for release via the NACJD website and/or through the options on our Restricted Data Details page. These options balance retaining the necessary analytic information while providing limited, controlled access to the data.

Depositors can contact NACJD staff with any questions about preparing data with confidential content for deposit, or to discuss Restricted Data or other options. NACJD staff are available via email at icpsr-help@umich.edu. Please add “NACJD” to the subject line of your inquiry.

Direct Identifiers

The most familiar type of personally identifiable information is direct identifiers. Examples of direct identifiers include:

  • Names
  • Addresses, including ZIP codes
  • Telephone numbers, including area codes
  • Social Security numbers
  • Other linkable numbers, such as driver’s license numbers, police badge numbers, and prisoner identification numbers.

This Health Insurance Portability and Accountability Act (HIPAA) Privacy Rule provides guidance regarding direct identifiers and methods for de-identification.

Indirect Identifiers

Variables that can also be problematic are indirect identifiers used in conjunction with publicly available information to identify individual respondents. Decisions about providing these variables depend on a dataset’s content and the nature of the research subjects. Examples of indirect identifiers include:

  • Detailed geographic information (e.g., State, county, or census tract of residence)
  • Organizations (to which the respondent belongs)
  • Educational institutions (from which the respondent graduated and the year of graduation)
  • Exact occupations
  • Place where the respondent grew up
  • Exact dates of events (birth, death, marriage, divorce)
  • Detailed income
  • Offices or posts held by the respondent