International Journal of Play Therapy Vol. 27, Iss. 4,  (Oct 2018): 187-197. DOI:10.1037/pla0000084 This study focused on examining the treatment effect associated with two 12-session interventions (child-centered play therapy and nature-based child-centered play therapy) among early elementary schoolchildren (N = 8) who had an attention-deficit/hyperactivity disorder diagnosis.. To read the full article, log in using your NHS OpenAthens details.