Impact

Impact is about the influence of libraries and their services on individuals and/or on society

Definition

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 contact with library services (British Standard 3.25).

Identifying impact 

Bear these two key issues in mind about impact and knowledge and library services:

• the change (impact) can be tangible or intangible and may be difficult to quantify
• the impact may be difficult to separate from other influences and prove that the impact was due to the library

Knowledge and library services may only contribute to an impact rather than be solely responsible for it (e.g. length of stay, patient care). 

Proxy measures 

Surrogate or proxy measures of impact may be used to monitor impact. For example, output data such as attendance, or satisfaction with a service. Proxy measure will not demonstrate actual impact.

The contributions of KLSs can be monitored via: 

• solicited methods such as questionnaires, interviews   
• observations that are either structured or informal   

Critical incident technique 

The critical incident technique is useful for tying the impact to one particular use of the library and knowledge service.   

Ideally these methods should be used in combination for reliability. 

The impact of sample size and low response rates 

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, by Urguhart et al. in Reflections on the value and impact of library and information services: Part 2: impact assessment, for samples of physicians to be confident about the claims being made.

Tools to measure impact 

Before measuring impact, check that it is really impact you want to measure. The terminology is complex and often used interchangeably.

A range of tools is available that can be used to measure impact.

The logic model visualises inputs, outputs and outcomes which demonstrate impact.

The impact case study highlights the impacts of particular uses of library services.

We have developed an impact case study template for use by NHS knowledge and library services and others who may be interested. 

See also  Public Health England's Impact Stories. Provide good examples of how case study evidence can be presented. 

Infographics are visual tools to demonstrate impact results.

CILIP: the library and information association has provided an impact toolkit for its members.