Logic analysis
7.3 Foundations of logic analysis
A fundamental principle of logic analysis is to validate or identify the theory of intervention to make sure it is based on evidence and not on beliefs.
As evaluators, we should also question the validity of the intervention’s chain of action (validity of the means), and we should test the scientific plausibility of the program’s theory. In fact, it could be argued that program theory does not really reflect how the intervention produces the intended outcomes, but rather, stakeholders’ perceptions and beliefs, right or wrong, about the mechanisms that operate between the delivery of the intervention and the intended outcomes. The whole evaluation is then built on the consensus reached on participants’ beliefs and perceptions. But what do we do as evaluators if these are incomplete or, worse, if they are wrong? Can we really build valid evaluations based on the prior analysis of a program’s theory that reflects what people think, but not what the intervention does (Chen, 1990a, 1990b)? (as cited in Brousselle & Champagne, 2011, p. 69)
Program theory is:
a specification of what must be done to achieve the desired goals, what other important impacts may also be anticipated, and how these goals and impacts would be generated. (Chen, 1990, p. 43)
central to evaluation practice and has evolved as a response to black box evaluations and the related difficulty of results interpretation (Funnell and Rogers, 2011). (as cited in Brousselle et al., 2022, p. 337)
Logic analysis goes beyond drafting the program theory, it provides a process for analyzing its plausibility for achieving the expected results.
Logic analysis is useful for better understanding the intervention’s strengths and weaknesses and for analyzing whether the intervention is designed in a way that can logically produce the desired results (Champagne et al., 2009). Furthermore, it allows us to assess the strength of the causal link between the intervention and the intended effects. A strong causal chain is a precondition for conducting an effect analysis; even so, in the absence of such a chain, logic analysis can provide insights into the intervention’s potential (although that potential in no way guarantees the effects will be achieved). (as cited in Brousselle & Champagne, 2011, p. 70)
