 Two studies on dyadic developmental psychotherapy have been published by Becker-Weidman, the second being a four-year follow up of the first.Prior and Glaser state Hughes' therapy reads as good therapy for abused and neglected children, though with "little application of attachment theory", but the advocacy group ACT and the Task Force place Hughes within the attachment therapy paradigm.In 2004, Saunders, Berliner and Hanson developed a system of categories for social work interventions which has proved somewhat controversial.