This critical difference between these two models can perhaps be best illustrated by the different predictions they would make about the target of treatment of unaffected individuals at high risk of PD because of elevated EP scores. The mediational model would suggest that treatments could be targeted toward reducing levels of EP with the conviction that a lowering of disease risk would necessarily follow. The risk-indicator model, by contrast, would indicate that treatments should be directed toward correcting the underlying genetic liability, as there would be no guarantee that interventions that reduced EP would prevent illness onset.
