| Active Ingredient | Uses based on scientific evidence | Grade* |
| clay | there is not enough scientific research to support a recommendation for play with modeling clay as an effective therapeutic intervention in children with constipation and encopresis (involuntary bowel movement). | c |
*Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use;
F: Strong scientific evidence against this use.