Confidentialised Unit Record Files
The ABS is permitted under the Census and Statistics Act 1901 to release unit record data provided this is done: ‘...in a manner that is not likely to enable the identification of a particular person or organisation to which it relates.’ These microdata are released as Confidentialised Unit Record Files (CURFs).
The unit records are protected from identification in a number of ways. The name, address and all other information which would enable an individual or business to be easily identified are removed. Some records with unusual characteristics which might make them identifiable from the crowd are altered to more usual values and some very unusual records (the tall poppies) are removed altogether.
A second line of protection from identification is control of the mode of access to more detailed data by the ABS and restrictions on how the data may be used and limitations on the size and nature of outputs obtained from unit record data.
The third line of protection is a binding legal undertaking from each users and the CEO of his/her organisation regarding the use to which the CURF is to be applied, including an undertaking that no attempt will be made to identify the units to which the data applies, backed up by logging / auditing the use of the CURF to ensure the undertaking is followed.
The least detailed unit record files are available on CD-ROM. These may be accessed by the client on his/her own computer, but an analysis based on this kind of CURF is, like the data, somewhat restricted.
More detailed CURFs may be accessed through the Remote Access Data Laboratory (RADL). This allows access from any computer with Internet connection. The CURF remains within the ABS premises, user activity is monitored and there are restrictions on the kind of queries permitted and the size and type of outputs.
The most detailed CURFs are available via the ABS Data Laboratory (ABSDL). This is for specialist applications requiring a high level of detail. Using the ABSDL, it may be possible to use data from collections where previously CURFs could not be produced. The ABSDL may allow users to integrate CURF data with other datasets in a way that does not identify individuals. User activity is kept under ABS supervision and although there is more freedom in the kinds of queries that are permitted, there are greater restrictions on the nature and size of outputs which can be removed from the ABS environment.
A CURF will be produced by the ABS only where there is a demonstrated user demand, and the CURF specifications comply with confidentiality requirements. The release of a CURF is at the discretion of the Australian Statistician. Depending on content, some CURFs may be available only via the RADL or ABSDL services. All Basic CURFs available on CD-ROM can also be accessed through the RADL service, subject to the clearance auditing procedures applicable to all RADL access to CURFs.
If you would like access to one or more CURFs, all the details of the conditions of access and the undertakings required, costs, etc. including the CURF user training manual (required reading for all CURF users) are available on the ABS web site <www.abs.gov.au> under Access to ABS CURFs.
For further information contact the National Information and Referral Service on 1300 135 070 or client.services@abs.gov.au.