Part 2- Understanding the Intervention Logic
Part 2 of this series, unpacks the Intervention Logic, outlining how it differs from a Theory of Change and the role it plays in mapping programmes, evaluating outcomes, and supporting clear communication with stakeholders.
This post is part two of a two-part series, with part one focusing on the Intervention Logics’ counterpart, the Theory of Change.
The Intervention Logic is a close cousin of the Theory of Change. These two models belong to a family of diagrams that includes Logic Models, Programme Logics, Programme Theories, Benefits Maps, Outcomes Frameworks, and more. This assemblage of terms can create confusion, especially as there is not always a clearly delineated differentiation between them and, in some contexts, they are used interchangeably. However, although the terms Theory of Change (ToC) and Intervention Logic (IL) lack a universal, unifying definition and format, they do have some generally agreed-upon key points of difference which can support a foundational understanding of each. These general differences are highlighted below, along with their definitions within an ImpactLab context.
Where do the Theory of Change and the Intervention Logic diverge?
A Theory of Change and Intervention Logic share a common core. They both demonstrate the chain, or flow, of direct programme inputs to the outcomes that the programme intends to achieve; they both use this flow to illustrate the causal, if-then relationships that lead to the stated outcomes; and they both support service providers to evaluate and analyse the effectiveness of their programmes. Despite this considerable overlap, the ToC and the Intervention Logic do serve distinct purposes and meet differing strategic needs.
- Scope: Generally, the scope of a ToC is broader than that of an Intervention Logic. A ToC takes a whole landscape into its view, considering factors like the context within which a programme is operating, external influences that may impact programme outcomes, and ripple-effects of a programme that extend to intergenerational or community outcomes. In contrast, an Intervention Logic is targeted towards a specific programme and participant journey, describing only the chain of influence that can be directly tied to the programme. The Intervention Logic creates clear boundaries around a contained system, mapping only what takes place within that system; a ToC can explore how other systems interact with this bound programme system.
- Structure: The broader scope of the ToC enables a structure which can be much more flexible and fluid than its Intervention Logic counterpart, with room for non-linear and vertical pathways. A ToC offers more room for abstracted, lateral thinking, whereas an Intervention Logic is much more predictable and standardised, with pre-determined pathway flows. Consequentially, all Intervention Logic’s will follow roughly the same template, where the templates of ToC’s can vary significantly.
Neither method is better than the other; each offers benefits and serves distinct communicative purposes – the flexibility of a ToC may be better for strategic visualisation and capturing higher-order, rippling impact, whereas the structured Intervention Logic may serve to better communicate the immediate and direct outcomes of a programme to funders and other key stakeholders.
How ImpactLab understands this difference
At ImpactLab, ToC’s and Intervention Logic’s are broadly understood through the delineations identified above. However, there is another crucial difference in our internal framing and interpretation; a difference in ownership.ToC’s are developed and owned by the service provider. It is an articulation of their own ambitions, approaches and strategies, laying out the change journey in their own words and drawing attention to those points that they see as affecting impact.
In contrast, an Intervention Logic presents a programme through the lens of an independent, third-party Analyst. When an Analyst works with a service provider, all that they come to know about a programme through qualitative and quantitative data analysis and academic research is synthesised within the Intervention Logic. Accordingly, the Intervention Logic serves as an external analysis of a programme which can be delivered to internal and external funders with confidence, providing:
- Consistent, standardised structure: At ImpactLab, all Intervention Logic’s follow the same base structure, with each column having clearly defined meanings, allowing for consistent interpretation and readability.
- Evidence-based development: A ToC can be, and often is, evidence-based; however, as ToC’s are flexible in their design and purpose, this is not always the case. The Intervention Logic’s created by ImpactLab explicitly highlight where change has been informed by evidence through analysing provider data and reviewing the available academic literature.
- Objective, third-party analysis: Perhaps most importantly, the Intervention Logic’s developed by ImpactLab represent an independent, third-party view into a programme. They give service providers a useful tool that have been externally validated, delivering trust and integrity when communicating a programme’s value to external stakeholders.
While a ToC and Intervention Logic share many similarities, they each occupy their own niche within the broader landscape of programme mapping and evaluation tools. What is right for each service provider depends on what communicative, evaluative and strategic purposes they are meeting. But, if an Intervention Logic is right for you, consider connecting with ImpactLab for your independent, third-party evaluation.
This post is part two of a two-part series, with part one focusing on the Intervention Logics’ counterpart, the Theory of Change.
The Intervention Logic is a close cousin of the Theory of Change. These two models belong to a family of diagrams that includes Logic Models, Programme Logics, Programme Theories, Benefits Maps, Outcomes Frameworks, and more. This assemblage of terms can create confusion, especially as there is not always a clearly delineated differentiation between them and, in some contexts, they are used interchangeably. However, although the terms Theory of Change (ToC) and Intervention Logic (IL) lack a universal, unifying definition and format, they do have some generally agreed-upon key points of difference which can support a foundational understanding of each. These general differences are highlighted below, along with their definitions within an ImpactLab context.
Where do the Theory of Change and the Intervention Logic diverge?
A Theory of Change and Intervention Logic share a common core. They both demonstrate the chain, or flow, of direct programme inputs to the outcomes that the programme intends to achieve; they both use this flow to illustrate the causal, if-then relationships that lead to the stated outcomes; and they both support service providers to evaluate and analyse the effectiveness of their programmes. Despite this considerable overlap, the ToC and the Intervention Logic do serve distinct purposes and meet differing strategic needs.
- Scope: Generally, the scope of a ToC is broader than that of an Intervention Logic. A ToC takes a whole landscape into its view, considering factors like the context within which a programme is operating, external influences that may impact programme outcomes, and ripple-effects of a programme that extend to intergenerational or community outcomes. In contrast, an Intervention Logic is targeted towards a specific programme and participant journey, describing only the chain of influence that can be directly tied to the programme. The Intervention Logic creates clear boundaries around a contained system, mapping only what takes place within that system; a ToC can explore how other systems interact with this bound programme system.
- Structure: The broader scope of the ToC enables a structure which can be much more flexible and fluid than its Intervention Logic counterpart, with room for non-linear and vertical pathways. A ToC offers more room for abstracted, lateral thinking, whereas an Intervention Logic is much more predictable and standardised, with pre-determined pathway flows. Consequentially, all Intervention Logic’s will follow roughly the same template, where the templates of ToC’s can vary significantly.
Neither method is better than the other; each offers benefits and serves distinct communicative purposes – the flexibility of a ToC may be better for strategic visualisation and capturing higher-order, rippling impact, whereas the structured Intervention Logic may serve to better communicate the immediate and direct outcomes of a programme to funders and other key stakeholders.
How ImpactLab understands this difference
At ImpactLab, ToC’s and Intervention Logic’s are broadly understood through the delineations identified above. However, there is another crucial difference in our internal framing and interpretation; a difference in ownership.ToC’s are developed and owned by the service provider. It is an articulation of their own ambitions, approaches and strategies, laying out the change journey in their own words and drawing attention to those points that they see as affecting impact.
In contrast, an Intervention Logic presents a programme through the lens of an independent, third-party Analyst. When an Analyst works with a service provider, all that they come to know about a programme through qualitative and quantitative data analysis and academic research is synthesised within the Intervention Logic. Accordingly, the Intervention Logic serves as an external analysis of a programme which can be delivered to internal and external funders with confidence, providing:
- Consistent, standardised structure: At ImpactLab, all Intervention Logic’s follow the same base structure, with each column having clearly defined meanings, allowing for consistent interpretation and readability.
- Evidence-based development: A ToC can be, and often is, evidence-based; however, as ToC’s are flexible in their design and purpose, this is not always the case. The Intervention Logic’s created by ImpactLab explicitly highlight where change has been informed by evidence through analysing provider data and reviewing the available academic literature.
- Objective, third-party analysis: Perhaps most importantly, the Intervention Logic’s developed by ImpactLab represent an independent, third-party view into a programme. They give service providers a useful tool that have been externally validated, delivering trust and integrity when communicating a programme’s value to external stakeholders.
While a ToC and Intervention Logic share many similarities, they each occupy their own niche within the broader landscape of programme mapping and evaluation tools. What is right for each service provider depends on what communicative, evaluative and strategic purposes they are meeting. But, if an Intervention Logic is right for you, consider connecting with ImpactLab for your independent, third-party evaluation.
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Part 2- Understanding the Intervention Logic
Part 2 of this series, unpacks the Intervention Logic, outlining how it differs from a Theory of Change and the role it plays in mapping programmes, evaluating outcomes, and supporting clear communication with stakeholders.
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