Insuring confidentiality of individual records in data storage and retrieval for statistical purposes

Much has been written about the question of privacy and the need for the protection of confidentiality of individual records in data storage and retrieval systems. The ability to insure confidentiality is a prime tool in the protection of privacy. The goal of this paper is to summarize from the point of view of a statistician some of the aspects and principles of confidentiality and some of the implications of these principles for computer-based storage and retrieval systems for statistical purposes. The remarks will have special relevance to open retrieval systems, that is, retrieval systems in which customers for information retrieval are the general public, or perhaps specified agencies or groups or individuals, and these customers can retrieve any desired statistics from the confidential records in the files subject to a review to insure that the output conforms to prescribed rules designed to avoid disclosure of individual information. These rules may be concerned with the minimum number of cases on which an individual statistics or frequency count is based or with other aspects, as is discussed later. The access to the data may be restricted to certain authorized types of data through control passwords or keys.