Directed acyclic graph (DAG) representing the natural indirect effect (that is mediated by changes in bone marrow lesion, synovitis, patella and wrist sensitization, or depressive symptoms; X to Y pathway through M) and the natural direct effect (that is not mediated; X to Y pathway not passing through M) of weight loss on knee pain improvement.
BML, bone marrow lesion; PPT, pressure pain threshold; CES-D, Center for Epidemiologic Studies Depression scale