Methodology
The methodology behind the Impact Evaluation Standard
The Impact Evaluation Standard is a standard set of rules which enables organisations to bring consistency and additional rigour to their reporting of social value for individual projects or their entire organisation, encompassing local economic benefit, sustainability and community benefit aspects.
The framework can assist organisations in the completion of an indicative Social Return on Investment alongside a forecast Socioeconomic Cost-Benefit Analysis by:
- Providing a comprehensive and standardised list of metrics as a guide to typical social value outputs and outcomes
- Acting as a prompt to help steer what resources (inputs) and activities might be required to achieve those outputs and outcomes
- Where possible or relevant, providing financial proxy values for either the economic benefit of those outcomes or the forecast social value of those outcomes.
Each release of the Impact Evaluation Standard is versioned. Data captured under previous versions remains unchanged, ensuring consistency in historical reporting while allowing new reporting periods to align with updated standards.
The Impact Evaluatiobn Standard is reviewed annually to reflect updates to UK government policy, the Social Value Model, and underlying datasets. Updates are governed through a structured review process and released as a new version.
An overview of the metrics and proxy values included in the Impact Evaluation Standard is provided below.
Missions
The 2025 version of the Impact Evaluation Standard consists of a series of over 130 metrics – measures of the social value outcomes intended e.g. the number of employment opportunities created, or reduction in CO2 emissions.
These metrics are all aligned to the Social Value Model guidance from PPN002 and each fall within one of 5 key missions:
The metrics directly correlate to the 52 Reporting Metrics stipulated in the Social Value Model, but also extend these to give additional depth by adding other aspects noted in the Social Value Model documentation and/or other commonly used metrics in social value reporting.
Mission 1: Kick start economic growth
Outcome 1: Fair work
Outcome 2: Skills for growth
Outcome 3: Resilient, innovative and flexible supply chain
Mission 2: Make Britain a clean energy superpower
Outcome 4: Sustainable procurement practices
Mission 3: Take back our streets
Outcome 5: Support the reduction in crime
Mission 4: Break down barriers to opportunity
Outcome 6: Employment and training for those who face barriers to employment
Outcome 7: Creating a pipeline of opportunities for the contract workforce, reducing barriers to entry for under-represented groups
Mission 5: Build an NHS fit for the future
Outcome 8: Increasing productivity through physical and mental wellbeing – in the supply chain and communities in the relevant area
Proxy Values
Many metrics have been given proxy values – indicative financial values of social impact or economic benefit that provide an additional way to quantify social value and evidence the impact to society.
Many social value calculators include proxy values – there is no single definitive source of these values. The proxy values in the Impact Evaluation Standard are UK-specific and have been derived by the Impact Evaluation Standard steering committee and working groups in line with HM Treasury Green Book Guidance and are drawn from different sources and studies.
For instance:
- Primary sources, are the most preferrable and are government research and studies – such as data from the ONS or the Manchester Unit Cost Database.
- Secondary sources are university or thinktank studies
- Tertiary sources, used where no studies exist, are created via independent research undertaken by the standard or external consultants.
Aligned with UK government guidance PPN 002 and the Social Value Model
This Procurement Policy Note (PPN) launches a new model to deliver social value through government’s commercial activities. Central government organisations should use this model to take account of the additional social benefits that can be achieved in the delivery of its contracts, using policy outcomes aligned with this Government’s priorities.
Social value should be explicitly evaluated in all central government procurement, where the requirements are related and proportionate to the subject-matter of the contract, rather than just ‘considered’ as currently required under the Public Services (Social Value) Act 2012. Unnecessary burdens should not be placed on commercial teams or suppliers.
