Clay Therapy Versus Mandala Coloring for Youth’s Emotional Well-Being: An Active-Comparator Randomized Controlled Trial

This study compared clay therapy (CT) and mandala coloring (COM) on emotion regulation among 100 Hong Kong secondary school students. Participants were randomized to six weekly 2-hour CT or COM sessions, with outcomes assessed at baseline, post-intervention, and 6-week follow-up. Repeated-measures ANOVA revealed significant time × group interactions favoring CT for positive affect, total hope, and its subscales with small effect size, partial η2 = .03–.04. CT significantly reduced anxiety and depression immediately, and showed further improvements in positive affect, hope, anxiety, and resilience at follow-up. COM produced immediate improvements in positive affect, hope, and resilience, but most effects diminished by follow-up. Overall, COM offered more immediate short-term benefits, whereas CT demonstrated slower but more sustained improvements over time.