Factors independent of a public intervention which are partly or entirely the cause of changes observed among beneficiaries (gross effects). A confounding factor can hinder or amplify an expected impact. For example, employment increased by 10% in a group of assisted firms. However, this increase could not be imputed entirely to the public intervention because the assisted firms also benefited from a favourable macro-economic context (confounding factor). In another example, close to 80% of the trainees found a job after one year. However, this high placement rate was partly imputable to the initial qualifications of the trainees which were very high at the time of their recruitment (skimming-off effect). When a causality analysis is carried out as part of an evaluation, it distinguishes between effects imputable to the public intervention (net effects) and those imputable to confounding factors. Related Terms: Concurrent factor, Extraneous factor, Exogenous factor BACK