Dealing with small numbers and the risk of disclosure
Protecting confidentiality applies to more than just individual-level data which might contain personal information (e.g. name, date of birth, address or NHS number). The principles of confidentiality should also be considered with summary data, such as numbers in tables, particularly when numbers are small. The following briefing provides a summary of the confidentiality issues which can arise when providing data involving small numbers, and describes the methods commonly used to deal with them: Maintaining confidentiality in disseminated data (279.22 KB)
The legal context for use of health data
The Parliamentary Office of Science and Technology (POST) publishes a number of 'POSTnotes' each year; short briefings focussing on current issues in science and technology. POSTnote 474 from July 2014 provides an excellent summary of the key legislation relevant to the secondary use of health-related data for public health purposes. The briefing also succinctly summarises a number of sources and types of health data and a range of secondary uses within and outside the NHS.