Moving beyond statistical association to establish causal relations i non-trivial. Their very first reference is Judea's Pearl's work who pioneered this domain

Moving beyond statistical association to establish causal relations i non-trivial. Their very first reference is Judea's Pearl's work who pioneered this domain. Pearl, J. Causality: Models, Reasoning, and Inference (Cambridge University Press, 2000) He also has a slightly more accessible book (The book of Why). He argues that most of classical statistical analysis is but the first of three levels (association), with intervention (what if) and counterfactual analysis being the path to understanding.