This video guide, produced by UNICEF, outlines three broad strategies for causal attribution: 1) estimating the counterfactual; 2) checking the consistency of evidence for the causal relationships made explicit in the theory of change; and 3) ruling out alternative explanations, through a logical, evidence-based process.
Sources
UNICEF (2014), Causal Attribution Video. Retrieved from: http://www.youtube.com/watch?v=AGF_daE0ce8