Assumptions in theories of change

This paper argues that assumptions in a theory of change are the causal connections, events, and conditions that need to be realized for the intervention to work. Using an example of an intervention aimed at improving educational outcomes for girls in a conservative region, two kinds of assumptions are discussed: cause-effect assumptions and causal-link assumptions. Implications for the use of theories of change, including their use in setting causality and the utility of evidence in argument for learning about and testing assumptions are also discussed. The need for an explicit description of what is meant by the term 'assumptions' in association with a theory of change is also highlighted.

Testing theory of change assumptions of health behavior change interventions: A blended approach exploring local contexts

This paper used a blended approach that involves multiple techniques to, first, test a set of assumptions around a health behavior change communication intervention theory of change (ToC) and, second, surface some unidentified assumptions involving the local context. The intervention was integrated with women's self-help groups (SHGs) in Uttar Pradesh, India. The key assumption tested in this paper was the linkage between SHG membership, program exposure, and maternal, newborn, and child health practices. Learnings were substantiated through empirical investigations, including structural equation modeling and mediation analysis, as well as 'co-learning' workshops within the community. The workshops aimed to capture and interpret the heterogeneity of local contexts through deep dialogs with the community and program implementers at various levels. Statistical analyses indicated a significant association between the amount of women's program exposure and their health practices. SHG membership was shown to affect maternal health practices; however, it did not have a direct effect on neonatal or child health practices. The 'co-learning' workshops revealed crucial aspects, such as prevailing socio-cultural norms, which prevented pregnant or recently delivered women from participating in SHG meetings. This paper encourages evaluators to work with the community to interpret and co-construct meaning in unpacking the contextual forces that seldom appear in the program ToC.

Exploring how individuals complete the choice tasks in a discrete choice experiment: an interview study

Background

To be able to make valid inferences on stated preference data from a Discrete Choice Experiment (DCE) it is essential that researchers know if participants were actively involved, understood and interpreted the provided information correctly and whether they used complex decision strategies to make their choices and thereby acted in accordance with the continuity axiom.

Methods

During structured interviews, we explored how 70 participants evaluated and completed four discrete choice tasks aloud. Hereafter, additional questions were asked to further explore if participants understood the information that was provided to them and whether they used complex decision strategies (continuity axiom) when making their choices. Two existing DCE questionnaires on rotavirus vaccination and prostate cancer-screening served as case studies.

Results

A large proportion of the participants was not able to repeat the exact definition of the risk attributes as explained to them in the introduction of the questionnaire. The majority of the participants preferred more optimal over less optimal risk attribute levels. Most participants (66 %) mentioned three or more attributes when motivating their decisions, thereby acting in accordance with the continuity axiom. However, 16 out of 70 participants continuously mentioned less than three attributes when motivating their decision. Lower educated and less literate participants tended to mention less than three attributes when motivating their decision and used trading off between attributes less often as a decision-making strategy.

Conclusion

The majority of the participants seemed to have understood the provided information about the choice tasks, the attributes, and the levels. They used complex decision strategies (continuity axiom) and are therefore capable to adequately complete a DCE. However, based on the participants’ age, educational level and health literacy additional, actions should be undertaken to ensure that participants understand the choice tasks and complete the DCE as presumed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-016-0140-4) contains supplementary material, which is available to authorized users.