National Longitudinal Survey of Children and Youth: Confidentiality and remote access

In 1994, Statistics Canada introduced a new longitudinal social survey that collects information from about 23,000 children spread over 13,500 households. The objective of the National Longitudinal Survey of Children and Youth is to measure the development and well being of children until they reach adulthood. To this end, the survey gathers together information about the child, parents, neighbourhood as well as family and school environment. As a consequence, the data collected for each child, is provided by several respondents, from parents to teachers, a situation which contributes to an increased disclosure risk. In order to reach a balance between confidentiality and the analytical value of released data, the survey produces three different microdata files with more or less information. The master file that contains all the information is only available by means of remote access. Hence, researchers do not have direct access to the data, but send their request in the form of software programs that are submitted by Statistics Canada staff. The results are then vetted for confidentiality and sent back to the researchers. The presentation will be devoted to the various disclosure risks of such a survey and to the tools used to reduce those risks.