The effectiveness of acceptance and commitment therapy (ACT) on neurotic perfectionism and internalized self-criticism in neurotic perfectionist girls: A single-case experimental study

Neurotic perfectionism has a variety of psychological consequences that should be considered in psychotherapy applications.   

The present study aimed to examine the effectiveness of acceptance and commitment therapy (ACT) on neurotic perfectionism and internalized self-criticism in neurotic perfectionist girls.

This study was conducted using a single-case quasi-experimental design with, concurrent multiple baseline. The research population consisted of neurotic perfectionist girls visiting counseling centers in Ahvaz in 2022. The participants were a sample of 5 girls selected using purposive sampling with a minimum cut-off score of 145 in the Neurotic Perfectionism Questionnaire (NPQ). The acceptance and commitment therapy (ACT) (Twohig & et al, 2021) was implemented in eleven 90-minute sessions. The participants completed the Neurotic Perfectionism Questionnaire (1994), and the Levels of Self-Criticism Scale (2004). The data were collected in three baseline, intervention, and three-month follow-up phases and analyzed using reliable change index (RCI), recovery percentage, and visual inspection.

The analysis of the recovery percentage showed the participants’ neurotic perfectionism 17.67 and internalized self-criticism 19.73 improved in the intervention phase and their neurotic perfectionism 36.25 and internalized self-criticism 49.90 increased in the follow-up phase. Moreover, the reliability change index of both variables in the post-treatment and follow-up phases was significant (P=0.05).

Considering the effectiveness of acceptance and commitment therapy in reducing neurotic perfectionism and internalized self-criticism by increasing psychological flexibility, this therapy can be used as an intervention method in neurotic perfectionist girls.