Performance indicators in NHS libraries

Performance indicators (PIs), workload statistics and accreditation are different ways to assess the quality of a library information service (LIS), and can be used together to give an overall picture of how well a LIS is performing its functions. PIs point out how something has been done. They are comparative values, often expressed partly as ratios or percentages, which indicate the quality or level of services and can be used to compare similar services, or the same service across time. PIs, performance ratios or performance standards are derived from performance measures, which show how much of it has been done. This paper looks at some aspects of performance measurement and suggests other areas for statistics collection in order to make better use of existing data, and considers the usefulness and derivation of PIs in NHS LIS.