Testing a Modular Online Self-Help Intervention in Adults with Clinical Perfectionism: A Randomized Controlled Trial

Objective: The current randomized controlled trial tested an online self-help interventionfor perfectionism that allowed participants to select their own treatment modules. Method: Participants with clinically significant perfectionism (N = 114; mean age = 33.9, 52.3% white,58.7% women) were randomly assigned to an online training (app) or active control condition(self-help book) and assessed at baseline, weekly during a 4-week intervention period, at 1-month follow-up, and at 6-month follow-up. Results: We found a smaller decrease inperfectionistic evaluative concerns in the app condition compared to the book condition (FMPS-Evaluative; ps = .002 to .007), but no differences were observed for perfectionistic striving(FMPS-Striving), psychological distress (DASS), quality of life (QOLS), psychologicalflexibility (Psy-Flex), and self-compassion (SCS-SF) by 6-month follow-up (Cohen’s ds forperfectionism subscales = -0.79 to -0.42 for the app,-1.12 to -0.88 for the book). Participants inthe app condition rated modules as being more helpful for meeting specific than general needs (t= -2.40, p = 0.021), suggesting they could “self-personalize” treatment by selecting modules thatfit their needs at the time of use. We did not find significant moderation effects for anydemographic or clinical variables. Conclusions: Both interventions led to similar improvementsover time and may serve as helpful low-intensity treatments for clinical perfectionism.Identifying variables that predict effective self-personalization may facilitate client-driventreatment selection. Limitations include lack of a waitlist control condition.