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Contribution Analysis: Coming of Age?



In this introductory article, a brief history and introduction to contribution analysis is provided to lay the stage for the articles that follow. At the heart of contribution analysis is the aim to be able to make credible causal claims about the contribution an intervention is making to observed results. The key role that theories of change play is noted, and what a useful theory of change ought to contain is discussed. The article then makes a link between the philosophical discussions on causality and contribution analysis through a discussion of contributory causes. It is argued that such causes, which on their own are neither necessary nor sufficient, represent the kind of contribution role that many interventions play: where there are a number of other influencing events and conditions at work in addition to the intervention of interest. Contribution analysis is an approach to confirming that an intervention is a contributory cause.
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DOI: 10.1177/1356389012451663
2012 18: 270Evaluation
John Mayne
Contribution analysis: Coming of age?
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DOI: 10.1177/1356389012451663
Contribution analysis: Coming of
John Mayne
Independent advisor, Canada
In this introductory article, a brief history and introduction to contribution analysis is provided
to lay the stage for the articles that follow. At the heart of contribution analysis is the aim to be
able to make credible causal claims about the contribution an intervention is making to observed
results. The key role that theories of change play is noted, and what a useful theory of change
ought to contain is discussed. The article then makes a link between the philosophical discussions
on causality and contribution analysis through a discussion of contributory causes. It is argued
that such causes, which on their own are neither necessary nor sufficient, represent the kind of
contribution role that many interventions play: where there are a number of other influencing
events and conditions at work in addition to the intervention of interest. Contribution analysis is
an approach to confirming that an intervention is a contributory cause.
causality, causal packages, contribution analysis, contributory causes, theories of change
This Special Issue focuses on contribution analysis (CA), a theory-based approach to evaluation
aimed at making credible causal claims about interventions and their results. Theory-based
approaches in evaluation have been discussed for many years (see Weiss, 1997a; Stame, 2004;
Rogers, 2007; White, 2009; Funnell and Rogers, 2011) and much has been written. Blamey and
Mackenzie (2007) make the useful distinction in theory-based approaches between realist evalua-
tions (Pawson and Tilley, 1997) and those approaches that develop an explicit theory of change.
The latter include Chen’s (1990) theory-driven evaluation, Weiss’s (1995, 2000) theory-based
evaluation and Mayne’s (2001, 2008, 2011) contribution analysis.
One result of the widespread interest in theory-based approaches is that there is no agreement on
the terms used and even some of the concepts. Nevertheless, there is consistency on the value of
theory-based approaches. They may be best thought of as a logic of enquiry for explaining
interventions that can complement and be used in combination with other designs and data collection
Corresponding author:
John Mayne, Canada 654 Sherbourne Rd, Ottawa, ON K2A 3H3, Canada.
18310.1177/1356389012451663Mayne: Contribution analysis: Coming of age? Evaluation
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Mayne: Contribution analysis: Coming of age? 271
techniques. Coryn et al. (2010) review practice with theory-based evaluation approaches over the past
decade, and White and Phillips (2012) review a number of ‘small n’ approaches to evaluation.
Most theory-based approaches rely on developing a theory of change, a logical model for an inter-
vention showing a results chain of how outputs are expected to lead to a sequence outcomes,
ing successive levels of desired effects. They seek to show how the intervention is expected to work or
make a difference. The theory of change is usually developed based on initial policy intentions, informed
then by a range of stakeholder views and information sources, including prior evaluations and research.
The theory of change is then verified to the extent that it matches what is observed to have happened.
CA lies within these theory-of-change approaches. I introduced the approach in 2001 (Mayne,
2001) and amplified it more recently (Mayne, 2011), and as noted in the 2011 publication, pub-
lished applications of CA were few, despite many references to the approach. Interest in CA was
evident at the 2010 EES Conference on Prague where a workshop on CA was given and several
papers presented (Lemire, 2010; Toulemonde, 2010; Wimbush and Mulherin, 2010). Subsequently,
the possibility of this Special Issue was raised.
I first discussed CA in the context of results monitoring systems (Mayne, 2001). The question I
was considering was what could be said about causality of an intervention when only monitoring
data were available. CA, it seemed to me, offered a reasonable way to make evidence-based causal
claims rather than being unable to say anything about causality – or worse, leaving readers to make
their own assumptions.
As I became more familiar with the range of theory-based approaches in evaluation – such as
those by Connell and Kubisch (1998), Davidson (2006), Gysen et al. (2006), Patton (2008b), Pawson
et al. (2004), Reynolds (1998) and Weiss (1995, 1997b) – it was clear than many shared common
features with CA. What was distinctive about CA was that it offered a more systematic way to arrive
at credible causal claims, and improve often weak evaluation practice when dealing with causality.
From an evaluation perspective, the issue was what could be done to make credible causal claims in
the absence of experimental approaches. Many evaluations seemed either to be silent on causality
or, perhaps worse, made causal claims based solely on the views of interviewees.
Contribution analysis: A quick overview
CA is based on the existence of, or more usually, the development of a postulated theory of change
for the intervention being examined. The analysis examines and tests this theory against logic and the
evidence available from results observed and the various assumptions behind the theory of change,
and examines other influencing factors. The analysis either confirms – verifies – the postulated theory
of change or suggests revisions in the theory where the reality appears otherwise. The overall aim is
to reduce uncertainty about the contribution an intervention is making to observed results through an
increased understanding of why results did or did not occur and the roles played by the intervention
and other influencing factors.
One aspect of CA that has been noted is that it suggests a structured approach to the analysis
(White and Phillips, 2012). Six key steps are set out as shown in Table 1 (Mayne, 2001). These
steps can also be part of an iterative approach to building the logic and evidence for claiming that
the intervention made a contribution.
While Table 1 sets out a number of specific steps, as the articles in this Special Issue illustrate,
those who have made use of CA have usually modified these steps to best suit the circumstances they
face and the specific analytic methods they have used. CA is still a relatively new approach in evalu-
ation. In my view, it is good practice that a variety of approaches are being developed and explored.
CA, then, argues that if one can verify or confirm a theory of change with empirical evidence,
and account for major external influencing factors, then it is reasonable to conclude that the
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272 Evaluation 18(3)
intervention in question has made a difference. The theory of change provides the basis for the
argument that the intervention is making a difference, identifies weaknesses in the argument and
hence where evidence for strengthening such claims is most needed. Causality is inferred from the
following logic and evidence:
1. The intervention is based on a reasoned theory of change: the chain of results, and the
assumptions behind why the intervention is expected to work are plausible, sound, informed
by existing research and literature and supported by key stakeholders.
2. The activities of the intervention were implemented as outlined in the theory of change.
3. The theory of change is verified by evidence: the chain of expected results occurred, and
the assumptions held.
Table 1. Key Steps in Contribution Analysis.
Step 1: Set out the cause-effect issue to be addressed
Acknowledge the causal problem.
Scope the problem: determine the specific causal question being addressed; determine the level of
confidence needed in answering the question
Explore the nature and extent of the contribution expected
Determine the other key influencing factors
Assess the plausibility of the expected contribution given the intervention size and reach
Step 2: Develop the postulated theory of change and risks to it, including rival explanations
Set out the postulated theory of change of the intervention, including identify the risks and
assumptions and links in the theory of change,
Identify the roles of the other influencing factors and rival explanations
Determine how contested is the postulated theory of change
Step 3: Gather the existing evidence on the theory of change
Assess the strengths and weaknesses of the links in the theory of change
Gather the evidence that exists from previous measurement, past evaluations, and relevant
research (1) for the observed results, (2) for each of the links in the results chain, (3) for the other
influencing factors, and (4) for rival explanations.
Step 4: Assemble and assess the contribution claim, and challenges to it
Set out the contribution ‘story’: the causal claim based on the analysis so far
Assess the strengths and weaknesses in the postulated theory of change in light of the available
evidence, the relevance of the other influencing factors, and the evidence gathered to support rival
If needed, refine or update the theory of change
Step 5: Seek out additional evidence
Determine what kind of additional evidence is needed to enhance the credibility of the contribution
Gather new evidence
Step 6: Revise and strengthen the contribution story
Build the more credible contribution story
Reassess its strengths and weaknesses
Revisit Step 4
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Mayne: Contribution analysis: Coming of age? 273
4. External factors – context and rival explanations – influencing the intervention are assessed
and are either shown not to have made a significant contribution or, if they did, their rela-
tive contribution is recognized.
In the end, a conclusion is reached – a contribution claim about whether the intervention made a
difference as expected. To summarize:
Contribution claim = a verified theory of change + other key influencing factors accounted for.
What does a contribution claim look like? The result of a CA is rarely definitive proof.
Causality in relation to socio-economic interventions is usually of the probabilistic form: that the
intervention is most likely to have made a difference. CA provides an argument with evidence
from which it is reasonable to conclude with confidence that the intervention has made a contri-
bution and why. It builds a compelling case – a warrant – about the contribution being made:
The aim is to get what Hendricks (1996) call ‘plausible association’: whether a reasonable person would
agree from the evidence and argument that the program has made an important contribution to the observed
result. (Mayne, 2011: 62)
While the focus has often been on using CA to make causal claims, as implied in my earlier
articles, and as the articles in this Special Issue amply point out, CA also has other uses. Wimbush
et al. in this issue discuss using CA approaches as a participatory tool in planning for results and
evaluation systems to enhance learning and understanding about intervention being planned and
reviewed. Leeuw in this issue discusses using CA approaches to be able to assess the likelihood
that a proposed policy initiative will work.
The Special Issue is evidence of both a growing CA practice and a continuing discussion and
debate about making use of CA and related theory-based approaches.
Contribution rather than attribution
There has been discussion and possible confusion between the terms attribution and contribution. Many
authors make a useful distinction between these terms (Patton, 2008a; Stern et al., 2012). In much of the
literature, attribution is used to both identify with finding the cause of an effect and with estimating quan-
titatively how much of the effect is due to the intervention. The term contribution is used here in the fol-
lowing way: in light of the multiple factors influencing a result, has the intervention made a noticeable
contribution to an observed result and in what way? The authors in this Special Issue adhere to this usage.
Useful theories of change
Critical to CA is the development of a well thought-out and credible theory of change. In my view,
a good theory of change goes well beyond a results chain or logical framework. I would argue that
a complete theory of change is embedded in the context of the intervention, and is developed incor-
porating the perspectives of key stakeholders, beneficiaries and the existing relevant research.
Theories of change should include:
• a results (causal) chain showing the basic logic of the intervention;
• the underlying assumptions behind the links in the results chain;
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274 Evaluation 18(3)
• an elaboration of the risks to each of these links;
• identification of unintended effects; and
• identification of other key explanatory factors (rival explanations).
Figure 1 illustrates the various components of a theory of change.
The theory of change is dis-
played deliberately as a quasi-linear process, but allows for feedback loops as needed. A ‘sort of
linear theory of change facilitates both arriving at causal claims and communicating the performance
story of the intervention. The assumption boxes can be used to reduce the number of explicit links
that might otherwise be needed in a theory of change. Other explanatory factors (rival explanations)
may be different for different links or may apply to the overall causal logic of the intervention. The
vertical ‘activities and outputs’ box allows for an implementation theory to be shown (i.e. the activi-
ties and outputs that are going to be delivered, perhaps over time, to implement the intervention).
Theories of change as causal packages
The logic used for making causal contribution claims outlined above was not related directly to the
literature on causality. There is a large and active literature on the issue of causation, and over
centuries now, a number of different perspectives have been developed to explain and understand
Final Outcomes
Assumptions: How do the intervention outputs
expect to result in or effect the immediate,
intermediate and inal outcomes? What has to
happen? What contextual factors inluence
these processes?
Risks : Risks to the link not occurring.
Assumptions: How are immediate
outcomes expected to producethe
intermediate outcomes? What has to
happen? What contextual factors
inluence these processes?
Risks: Risks to the link not occurring.
Assumptions: How are intermediate
outcomes expected to producethe
inaloutcomes? What has to
happen? What contextual factors
inluence these processes?
Risks: Risks to the link not occurring.
Other Explanatory
Factors/Rival Explanations:
Socio-economic factors; other
can differ for different
Activities and Outputs
Figure 1. Displaying a theory of change.
Assumptions are events and conditions that need to happen for the link to work. They are developed from a mix of
stakeholder and social science theories and research.
Risks are external event and conditions that could put the causal link at risk.
Other Explanatory Factors are other factors or conditions that might help explain the occurrence of the observed result
other than the influence of the intervention.
Unintended effects are positive or – more usually – negative unanticipated effects that occur as a result of the
interventions activities and results.
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Mayne: Contribution analysis: Coming of age? 275
causation, of which counterfactual approaches are only one. A recent study on impact evaluation
that I participated in commissioned by DFID (Stern et al., 2012) provides a discussion of these
different bases for causal inference. I would like to discuss how CA relates to the causality litera-
ture, many ideas of which arose during the work on the DFID-funded project. This has the potential
to suggest ways that we can further deepen and systematize CA within evaluation practice.
Causality involves relationships between events or conditions, and is often discussed in terms
of necessary and sufficient conditions. When we say that X ‘caused’ Y, we can mean that X is:
• Necessary but not sufficient.
A person must be infected with HIV before they can develop AIDS. HIV is therefore a
necessary cause of AIDS; however, since every person with HIV does not contract
AIDS, it is not sufficient.
• Sufficient but not necessary
Decapitation is sufficient to cause death; however, people can die in many other ways.
• Both necessary and sufficient
A gene mutation associated with Tay-Sachs is a both necessary and sufficient cause for
the development of the disease, since everyone with the mutation will eventually
develop Tay-Sachs and no-one without the mutation will ever have it.
• Neither necessary nor sufficient – a contributory cause
Smoking heavily is a contributory cause of lung cancer – it is not a necessary cause
since there are other sources of lung cancer, nor is it a sufficient cause since not all
smokers suffer from lung cancer.
I would suggest that in ordinary discussions, ‘X causes Y’ is most often taken to mean suffi-
ciency. We mean either that in this case the event X resulted in Y, or that generally the phenomena
X results in Y, recognizing in either case that there may be other events that also could produce Y.
Necessity seems a less common use of the term ‘cause’ as it quite demanding, requiring that when-
ever there is the event Y then there is X. Causes that are both necessary and sufficient are even
more rare. On the other hand, contributory causes that are neither necessary nor sufficient on their
own are quite common.
It is clear that many interventions do not act alone and that the desired outcomes will be the
result of a combination of causal factors, including other related interventions, and events and
conditions external to the intervention. Indeed, many interventions are designed to be part of such
a ‘causal package’, and even if not so designed, their evaluation needs to take these other factors
into account. Cartwright and Hardie (2012) call these supporting factors, other events and condi-
tions that need to happen in order for the intervention to work, to make a difference.
In these instances, the key causal question becomes: was the causal package consisting of the
intervention plus supporting factors sufficient to produce the intended outcome? It is recognized
that there could be other ways that the desired outcome is brought about and hence the particular
causal package in question may not be necessary to achieve the desired outcome. In addition, we
would want to know if the intervention was a necessary part of the specific causal package. Perhaps
the desired outcome could be realized through the supporting factors without the intervention. I’ll
refer to the causal package with these two characteristics – sufficiency of the package and necessity
of the intervention as part of the package – as the intervention causal package.
If these conditions hold, then the intervention is a contributory cause and as such has ‘made a
difference’, as I would define it. That is, the intervention was a necessary element of the causal
package that produced the observed result. Box 1 sets out an example of a causal package related
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276 Evaluation 18(3)
to an intervention aiming to improve education outcomes for girls. It is clear in this example that
there are other ways of improving educational outcomes of girls, such as through offering extracur-
ricular help to girls.
What is of particular interest is that, as I have described them, theories of change are in fact
postulated causal packages, and more. They identify the supporting factors as assumptions and
identify the risks (the confounding factors) and, as well, set out the relationships between support-
ing factors and the intervention. The assumptions are the supporting factors needed for the theory
of change to work. Overall, a theory of change is a model of how the intervention is expected to act
as a contributing cause.
A theory of change can be constructed for the example in Box 1. Its outline would be something
like: teachers with more training and skills in educating girls would provide teaching that is more
attuned to girls’ needs and is of more interest to them, resulting in girls being more actively engaged
in studying and wanting an education. This will lead to better education outcomes for the girls
concerned. Among the assumptions here would be (1) that teachers want to help girls get a better
education and hence work to acquire new skills, (2) parents support their daughters more active
engagement in school, (3) girls are able to attend schools, and (4) are comfortable there.
In the philosophy literature, contributory causes are called INUS causes: an Insufficient but
Necessary part of a condition that is itself Unnecessary but Sufficient for the occurrence of the
effect (Mackie, 1974) and there is a large literature on contributory causes and causal packages,
which are often described as causal cakes or pies, showing the various components (slices) that
make up the package (see Cartwright and Hardie, 2012 and Stern et al., 2012, for discussions).
The discussion of contributory causes has here so far been in deterministic terms (i.e. a cause is either
sufficient or it is not). However, as noted earlier, the discussion needs to reflect the probabilistic nature of
causality in socio-economic phenomena. Mahoney (2008: 421) argues that ‘a treatment is a cause when
its presence raises the probability of an outcome occurring in any given case’. He introduces the useful
ideas of probabilistically necessary causes – ‘factors that usually or almost always have to be present for
the outcome to occur – and probabilistically sufficient causes – ‘a cause that much of the time on its own
will produce the effect’ (pp. 425–6). For many interventions being evaluated, these are more realistic
interpretations of the necessary and sufficient conditions discussed earlier.
In term of an intervention’s causal package, I will use the terms likely necessary to describe the
supporting factors, and likely sufficient to describe the sufficiency of the intervention causal
Consider an intervention aimed at improving the education outcomes for girls in a developing country,
through raising the knowledge, skills and awareness of teachers in schools.
Other supporting factors here might be:
the willingness of teachers to support the education of girls;
the support of parents for their daughters to attend schools and study at home;
the ability of girls to get to the schools;
the adequacy of the schools to accommodate girls.
The causal package here is the training provided to teachers plus the supporting factors. An evaluation
would want to know if this causal package worked, i.e. in this case were education outcomes for girls
improved as a result of the causal package, and since it is an evaluation of the intervention, was the
intervention a needed part of the causal package?
Box 1. Causal packages and making a difference
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Mayne: Contribution analysis: Coming of age? 277
package, meaning that in this case, the causal package most likely produced the observed result.
To show that the intervention is a contributory cause is to show that the intervention’s causal pack-
age is likely sufficient, and that the intervention is itself a necessary element of the sufficient
Indeed, in terms of causal packages, this is exactly what CA is able to do; i.e. confirming:
• that the expected result occurred;
• that the supporting factors – the assumptions for each link in the theory of change – have
occurred and together provide a reasonable explanation for the results that occur;
• that any other identified supporting factor that is present has been included in the causal
package, thereby potentially revising the theory of change; and
• that any plausible rival explanations
– external causal factors – have been accounted for.
Given that the assumptions may be likely necessary conditions, in a specific case not all may
have occurred. In this case an assessment is needed of whether the collection of supporting factors
(assumptions) actually occurring provides a reasonable explanation for the observed result. This,
plus the assessment of rival explanations, allows for the causal inference to be made as to whether
the intervention causal package (for a link in a causal chain) was sufficient. If it was and all the other
links in the causal chain are also confirmed, then the theory of change itself has been confirmed.
Data and evidence for the analysis comes from drawing on logic, critical thinking, and prior
research and asking relevant stakeholders whether they believe there were other causal factors
beyond the package at work. If other causal factors were believed to be at work, one would need
to seek out supporting evidence. Note that the links in a theory of change should comprise rela-
tively proximate cause and effects, making judgement and the use of logic and critical thinking
Consider the intervention described in Box 1 about enhancing the skills of teachers so as to
improve education outcomes for girls. Assume the additional training of teachers occurred and
subsequently, an increase in education outcomes for girls was observed. Did the intervention make
a difference? Was the additional training a contributory cause? To answer, the steps and assump-
tions in the theory of change would be examined to see if they occurred as expected. Did teachers
acquire and apply new skills? Were girls more engaged? Did parents support their daughters get-
ting educated? Further, were any other factors at play outside the postulated theory of change, in
particular were there any plausible rival explanations for the enhanced education outcomes, and if
so what were they? Possible rival explanations might include greater investment generally in edu-
cation, increasing teacher/student ratios or the arrival of the internet, providing possibilities for self
learning. If the theory of change is confirmed and no significant rival explanations found, then one
could conclude with confidence that the intervention did indeed make a difference.
I am arguing that the idea of contributory cause is a useful and relevant concept for many interven-
tions. It offers a practical approach to confirming that an intervention contributed to an observed
result and indeed made a difference. As such, it also offers one basis for future methodological devel-
opment of CA as a form of theory-based evaluation, building on the concepts of causal packages.
Articles in the Special Issue
The articles in this Special Issue provide a broad overview and discussion of the current state of
CA. The first few articles provide specific cases of applied CA. Delahais and Toulemonde describe
their five years of experience of CA in their evaluation practice. Using several examples, they
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278 Evaluation 18(3)
discuss how they operationalized key aspects of CA and particularly the contribution story. They
discuss the real challenges faced in carrying out a CA and the resources required. The authors also
argue for the need for better ways of presenting contribution stories and for standards for assuring
the quality of CA.
Lemire et al. begin the discussion of applied CA, describing how they have operationalized the
steps involved in the analysis, focusing in particular on how to account for other influencing fac-
tors and rival explanations. They propose a tool to do this – the ‘Relevant Explanation Finder’.
Wimbush et al. provide examples of the use of CA and CA concepts from Canada and
Scotland. They have used CA as a participatory process, which strengthens both conceptual and
practical understanding of planning/managing for outcomes and the related implementation and
change theories, thus helping to build collaborative capacity within and across participating
partner organizations.
After an insightful discussion of the debate in development evaluation about the use of experi-
mental designs versus theory-based approaches, Vaessen and Raimondo discuss an evaluation of a
UNESCO programme that is not amenable to experimentation. They discuss CA in relation to
impact evaluation pointing to both strengths and weaknesses, describe the formative evaluation
they conducted using a theory of change, and discuss their planned use of CA for the summative
evaluation. They also discuss the idea of contributory causes in CA as outlined in this introductory
Leeuw, in discussing theory-based and CA approaches, describes the application of several
tools that are likely to be new to most evaluators, addressing three problematic situations: (1)
building theories of change using software; (2) forecasting impacts by testing theories of change
with look-alike interventions and examining past implementation failures; and (3) developing ‘his-
torical’ counterfactuals. Leeuw argues that CA can be strengthened through the identification of the
mechanisms at work that visualization software can foster, through the examination of implemen-
tation failures in look-alike mechanisms, and through testing contribution stories using historical
counterfactuals and hypothetical question research.
The remaining two articles discuss various aspects of the concepts behind CA. Patton, after
outlining and discussing cases of how CA is used in evaluations, argues that it depends crucially on
critical thinking. CA requires careful and rational thinking about the factors and conditions behind
the links between interventions and their impacts. He presents a forceful argument that ‘rigorous
thinking supersedes rigorous methodology’ and discusses quality standards for rigorous thinking.
Sridharan and Nakaima end the Special Issue. They discuss a number of questions and chal-
lenges to those using theory-based and CA approaches that can help in the further development of
theory-driven evaluation and CA approaches. Questions such as: ‘What is a “good-enough” pro-
gramme theory? How does one build understanding and expectations about programme impact?
What does causality mean for complex interventions? How does learning occur? How does the
application of theory-driven evaluation approaches help generate an “ecology of evidence”? How
can evaluation methods be integrated directly with CA?’ are discussed within the context of an
ongoing dance/physical activity programme for health promotion and the questions set the stage
for future work on CA.
Final comments
My intent with this Special Issue is to widen the interest in and share the experiences with using
CA as a way of making causal claims about interventions in a credible and rigorous manner.
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Mayne: Contribution analysis: Coming of age? 279
The articles provide a wealth of ideas to further explore CA and many references that readers can
follow up. After a healthy gestation period, I do think that CA is coming of age.
This research received no specific grant from any funding agency in the public, commercial or not-for-profit
1. I am using the term outcomes to cover the sequence of results (or effects) – immediate, intermediate and
final outcomes – following the delivery of outputs. Final outcomes here are meant to include impacts as
the term is used in the development evaluation world.
2. In some cases two or more theories of change may emerge. Hansen and Vedung (2010) discuss using
multiple stakeholder theories of change.
3. In commenting on this introduction, Jos Vaessen suggested that attribution/contribution can be usefully
distinguished as follows. Attribution emphasizes the issues of whether or not and how much of a par-
ticular change can be attributed to an intervention. Contribution emphasizes the confluence of multiple
causal factors to a particular change and emphasizes the issues of whether or not and how an intervention
contributes to the change.
4. There is a wide variety of ways of depicting theories of change. Funnell and Rogers (2011) provide
numerous examples.
5. Note that I am distinguishing here between the sufficiency of a specific event such as an intervention, and
the sufficiency of a phenomenon.
6. Lemire et al. in this volume discuss a systematic way to explore other influencing factors and rival expla-
nations in CA.
7. If one were trying to get at attribution in this case, the evaluation issue would be: how much of the
increase in education outcomes is due to the training provided to teachers?
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Chen H-T (1900) Theory-Driven Evaluations. Newbury, CA: SAGE.
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community initiatives: progress, prospects, and problems. In: Fulbright-Anderson K, Kubisch AC and
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Davidson EJ (2006) Causal inference nuts and bolts. American Evaluation Association Annual Conference,
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Funnell S and Rogers P (2011) Purposeful Program Theory. San Francisco, CA: Jossey-Bass.
Gysen J, Bruyninckx h and Bachus K (2006) The modus narrandi: a methodology for evaluating effects of
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John Mayne is an independent advisor on public sector performance. He has been working with a number of
government, NGO and international organizations in various jurisdictions, on results management, evaluation
and accountability issues. He has authored numerous articles and reports, including several on contribution
analysis, and co-edited five books in the areas of programme evaluation, public administration and performance
monitoring. In 1989 and in 1995, he was awarded the Canadian Evaluation Society Award for Contribution to
Evaluation in Canada. In 2006, he was made a Canadian Evaluation Society Fellow.
by Mayne John on July 16, 2012evi.sagepub.comDownloaded from
... Of these approaches, contribution analysis (Mayne, 2011(Mayne, , 2012 provides guidance for recognizing how multiple contextual programs, events, and life circumstances work in concert with a program to jointly contribute to or even alternatively explain those outcomes. Causality is inferred from four key steps involving logic and evidence. ...
... The theory of change is then verified by evidence that the chain of expected results occurred and the assumptions held. Finally, external factors that influence the intervention are assessed and either shown not to have made a significant contribution, or if they did, the relative contribution is recognized (Mayne, 2012). ...
Many youth programs seek [DW1] to understand their influence over time on participant outcomes. This paper offers a methodology for measuring a participant’s perception of a program’s contribution amid their perception of other youth influences such as those from family, school, peer groups, hobbies, and other organized activities. The instrument built on the large body of work on youth influences in order to capture the dominant factors in development of the item bank. In addition to item development, the paper documents face validity followed by content assessment of items using a research panel, a principal component analysis using a second panel, and a full pilot with older teens in other summer intensive programs. The scale’s implementation for baseline and annual follow-up measures of an intensive summer research experience revealed stable and high relative contribution to older teen participants’ academic and career decision making over time. The final scale includes 19 items in 6 factors of family & religion; interests organized by others; adult responsibilities; school; arts; and interests organized by self. The scale proved to be responsive to changes in influences while remaining stable over time
... L'analyse de contribution (contribution analysis) se distingue dès ses premiers pas par une démarche humble et pragmatique : son objectif n'est pas de prouver les effets des interventions, mais bien de réduire l'incertitude quant à leur contribution, de façon à éclairer la décision. C'est ainsi qu'elle est progressivement devenue une approche particulièrement adaptée aux situations complexes, lorsqu'une contribution est plausible, mais n'est certainement ni séquentielle ni linéaire (Mayne, 2012), ou lorsqu'il est probable, dès le départ, que l'intervention ne soit pas le principal vecteur du ou des changements recherchés (Delahais et Toulemonde, 2017 la contribution. L'analyse de contribution fournit un effort particulièrement important d'identification des impacts en contexte; en contrepartie, elle ne prétend pas à établir des modèles généraux, mais plutôt les ingrédients et les circonstances pour leur utilisation (Delahais et al., 2020). ...
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Les approches sont des ensembles de propositions relatives à ce qui constitue une bonne évaluation. Elles combinent de nombreux éléments, et en particulier un cadre paradigmatique, des promesses en termes de résultats et d’usages potentiels, des prescriptions méthodologiques ainsi que des préconisations pratiques permettant de les mettre en œuvre; Les approches sont comme des blocs de construction d’une évaluation. S’appuyer sur des approches lors de l’élaboration d’une démarche évaluative ouvre le champ des possibles en matière d’évaluation, permet d’apporter de la crédibilité méthodologique et de mieux se comprendre entre parties prenantes de l’évaluation; Il existe de nombreuses approches, qui correspondent à des contextes et des attentes différentes, mais aussi à la vision du monde et aux valeurs des différentes parties prenantes, évaluateurs et évaluatrices y compris. Il faut donc choisir en conséquence celles qui conviennent.
... In practice however, such approaches may present financial, logistic and process-related challenges, if not also ethical and political issues (Bédéracarrats et al., 2020). Other methods can be used, limiting themselves to making credible causal claims about the contribution an intervention is making to observed results (Mayne, 2012). Indeed, impact is incredibly hard to prove. ...
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The interest in evaluation and impact assessment of the social and solidarity economy (SSE) is reaffirmed year upon year. In the recent decades however, demands have grown and changed the way SSE organizations report on their activity. We are moving from a culture of evaluation of processes and results to the development of an expertise in measuring economic, social and environmental impacts. This represents an opportunity of the SSE, but it also poses challenges. This special issue aims to contribute to understand the approaches being developed for the SSE and examine the incidences they have on organizational practices and overall representation of the sector. In this editorial introduction we introduce the research topic, describe the content of the current special issue, and conclude with possible directions for future research.
... While there is no explicit "control" against which to compare outcomes, the approach recognizes the need for a counterfactual and emphasizes the importance of considering alternative explanations for an observed outcome that are beyond the program's hypothesized contributions. Examples of theory-based approaches to evaluation include process tracing (Beach and Pedersen 2019) or contribution analysis (Mayne 2012). ...
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While the key role that policy plays in sustainable development has long been recognized, rigorously documenting the influence of research on policy outcomes faces conceptual, empirical and even political challenges. Addressing these challenges is increasingly urgent since improving policies—broadly defined—is at the heart of the structural transformation agenda. This paper describes the use of a new evaluation method—outcomes trajectory evaluation (OTE), based on both evaluation and policy process theory—to explore the influence of HarvestPlus, a large and complex research for development program focused on improving nutrition, on a specific policy outcome, namely the establishment of crop biofortification breeding programs in national agricultural research institutes in Bangladesh, India and Rwanda. The findings support claims of significant HarvestPlus contribution s to the establishment of the sure sustainability. The paper also discusses the pros and cons of the OTE approach in terms of both methodological rigor and program learning. In particular, the fact that HarvestPlus is a long-running program allows us to reflect on how a “backward looking” approach such as OTE builds on and complements the more “forward looking,” theory of change-based approaches that informed HarvestPlus programming and evaluation during its earlier, highly-successful phases. Such a long-run perspective is rare in development evaluation and it offers important lessons for how to think about and plan for evaluation over the course of a complex agriculture research for development program.
... (Marchal, Van Belle and Westhorp, n.d. [52]). Key steps in the approach include understanding the (implicit or explicit) theory of change of the intervention, developing and refining a set of context-mechanism-outcome (CMO) hypotheses, and using a variety of research methods, both qualitative and quantitative, to collect and analyse data on both the mechanisms and the outcomes (Westhorp, 2014[53]). ...
Introduced in the United Kingdom in 2012, Universal Credit (UC) is a welfare benefit that replaces six working-age ‘legacy’ benefits for out-of-work and low-income people. Designed with the aim of simplifying benefits and incentivising paid work, UC represents a deepening of conditionality in the British welfare state. Considering these developments, this paper quantitatively investigates the effect of UC on recipients’ life satisfaction. Data from the United Kingdom Household Longitudinal Study is analysed, primarily using a fixed-effects regression approach. Results reveal a significantly negative effect of UC recipience on life satisfaction. Robustness checks and alternative model specifications, including difference-in-differences and inverse probability weighting, confirm this finding. Additionally, mediation models give credence to the idea that UC also negatively affects life satisfaction indirectly by increasing psychological distress. Heterogeneity tests indicate that UC has a less negative effect on single parents’ life satisfaction compared to non-parents. Meanwhile, UC has a significantly more negative effect on the life satisfaction of people not in paid work (for reasons other than unemployment) than those in paid work. Discussion focuses on the potential effect of welfare conditionality specifically, and implications for future research and policy are explored.
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Despite significant efforts by the European Union (EU), Member States (MS), and Regions, the role of evaluation in the Cohesion Policy (CP) is limited. Issues that are associated with the appropriate selection of evaluation methods can be identified among the main causes. Thus, a guide is developed for the selection of evaluation methods, depending on the intervention type and evaluation criteria, which are specific to evaluation questions. In all the cases, it is proposed to combine various methods, as the complexity of the interventions, along with the participatory character of the CP, and the weaknesses of each method require their combined application. It is proposed to apply 22 methods, combining 3 to 7 of them for each of the 5 evaluation criteria (relevance, effectiveness, efficiency, utility, sustainability) and the 9 main types of the CP’s intervention. At the same time, issues that are associated with impact evaluations are clarified. It is highlighted that both the proposed combination of evaluation methods and the evaluative questions are indicative rather than restrictive. Their selection is directly connected to the needs of authorities on behalf of which the evaluation is conducted, as well as the special conditions, under which the intervention is implemented. The proposed guidelines may be useful to the stakeholders involved in the evaluation of the CP on a practical level, as well as for all who are involved in the evaluation of public policies broadly, as they enhance accountability, legitimacy, and informed decision‐making in all stages of the public policies lifecycle.
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The changing culture of public administration involves accountability for results and outcomes. This article suggests that performance measurement can address such attribution questions. Contribution analysis has a major role to play in helping managers, researchers, and policymakers to arrive at conclusions about the contribution their program has made to particular outcomes. The article describes the steps necessary to produce a credible contribution story.
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Theory-based evaluations have helped open the ‘black box’ of programmes. An account is offered of the evolution of this persuasion, through the works of Chen and Rossi, Weiss, and Pawson and Tilley. In the same way as the ‘theory of change’ approach to evaluation has tackled the complexity of integrated and comprehensive programmes at the community level, it is suggested that a theory-oriented approach based on the practice of realistic cumulation be developed for dealing with the vertical complexity ofmulti-level governance.
Over the last twenty or so years, it has become standard to require policy makers to base their recommendations on evidence. That is now uncontroversial to the point of triviality—of course, policy should be based on the facts. But are the methods that policy makers rely on to gather and analyze evidence the right ones? In Evidence-Based Policy, Nancy Cartwright, an eminent scholar, and Jeremy Hardie, who has had a long and successful career in both business and the economy, explain that the dominant methods which are in use now—broadly speaking, methods that imitate standard practices in medicine like randomized control trials—do not work. They fail, Cartwright and Hardie contend, because they do not enhance our ability to predict if policies will be effective. The prevailing methods fall short not just because social science, which operates within the domain of real-world politics and deals with people, differs so much from the natural science milieu of the lab. Rather, there are principled reasons why the advice for crafting and implementing policy now on offer will lead to bad results. Current guides in use tend to rank scientific methods according to the degree of trustworthiness of the evidence they produce. That is valuable in certain respects, but such approaches offer little advice about how to think about putting such evidence to use. Evidence-Based Policy focuses on showing policymakers how to effectively use evidence. It also explains what types of information are most necessary for making reliable policy, and offers lessons on how to organize that information.