According to the British Standard – Impact is about the influence of libraries and their services on individuals and/or on society. An easier way of thinking about impact is as the difference or change in an individual or group resulting from the cont act with library services (3.25);
There are two key issues to bear in mind in relation to impact and library services:
1) The change (impact) can be tangible or intangible and may be difficult to quantify
2) The impact may be difficult to separate from other influences and prove that the impact was due to the library service. It may only be possible for the library to contribute to an impact rather than be solely responsible (e.g. length of stay, patient care)
Surrogate or proxy measures of impact may be used to monitor impact e.g. output data such as attendance or satisfaction (but these will not demonstrate actual impact)
The contributions of library services can be monitored via solicited methods (questionnaires, interviews etc.), and through observations (structured or informal) . The Critical Incident Technique is useful for tying the impact to one particular use of the library service. Ideally these methods should be used in combination for reliability.
Care needs to be taken when making claims about impact generated from small sample sizes or low response rates (a minimum of 60% response rate has been recommended for samples of physicians to be confident about the claims being made) (Urquhart and Turner, 2016)
A range of tools are available that can be used to measure impact in health libraries
The logic model is a useful approach for visualising inputs, outputs and outcomes which demonstrate impact.
The impact case study is a useful way of highlighting impacts of particular uses of library services. We have developed a template for use by NHS Library and Knowledge Services and others who may be interested.
You may also be interested in the Public Health England Impact Stories which provide a good example of how case study evidence can be presented.
Infographics are visual tools to demonstrate impact results
Before measuring impact, check that it really is impact you want to measure, the terminology is complex and often used interchangeably
For CILIP members, CILIP have provided an impact toolkit via their VLE
We welcome comments and feedback. Please do not hesitate to contact us