With regard to employing DD method, let me inform you that i too employed the same dd method in a similar study and when the paper was submitted to WBER journal, the editor states as follows:
"I am afraid however that you face the same problems as many that it is very difficult to find credible counterfactuals. Using the double difference method does not solve the problem, as it very likely that SG participants not only differ in their initial level of welfare (which the DD method would correct for) but in their welfare dynamic. At the WBER, we strive to only publish papers that rigorously establish causal effects."
Given this opinion of the WBER Editor, what would be your opinion?