Objective: There is a large body of evidence for the efficacy of Cognitive Behavioral Therapy (CBT) in treating Functional Abdominal Pain Disorders (FAPD) in children. In most CBT interventions for FAPD, parents participate together with their children. However, only one study to date has examined targeting parents alone for treatment. The aim of the current study was to examine mediators of a parent-only CBT treatment incorporating social learning (SLCBT) for FAPD in children.

Methods: We examined mediators of child outcomes in an existing randomized controlled trial (n = 316) of parent-only social learning CBT compared to an education condition. Hypothesized mediators (parental protectiveness, perceived threat of pain, catastrophizing) were assessed at 3 months post-treatment, and outcomes (parent ratings of disability, quality of life, school absences, and health care visits) were assessed at 6 months post-treatment. Mediation analyses were performed using Hayes' PROCESS macro.

Results: Pain catastrophizing significantly mediated treatment effects for all outcomes (B ranged from -1.65 to 2.22). Reduction in pain threat was a significant mediator for all outcomes (B ranged from -1.84 to 3.13) except school absences and health care visits. Decrease in parental protectiveness mediated effects on disability and missed school (B ranged from -1.47 to 1.34). Mediation effects did not differ by in-person or remote delivery of SLCBT.

Conclusion: Changes in maladaptive parental thoughts and behaviors following parent-only SLCBT intervention appeared to mediate the effects of the intervention. Parental catastrophizing appears to be a particularly important target given that decreases in that variable mediated all outcomes.