The effect of internet-based acceptance and commitment therapy (iACT) on psychological well-being among working women with a pre-school child: A randomized controlled trial

Introduction: Working mothers with small child face work and life difficulties and show low psychological well-being (PWB). Objectives: This randomized controlled trial aimed to examine the effectiveness of a newly developed, fully automated internet-based Acceptance and Commitment Therapy (iACT) program, 'Happiness Mom,' on improving Ryff's PWB of working mothers with a preschool child. Methods: The eligible participants were working mothers with at least one preschool child and were randomly assigned to either an iACT intervention group (n = 424) or a wait-list control group (n = 417). The intervention contained eight modules for 10 weeks. Primary outcomes were measured in six dimensions of Ryff's PWB (Ryff, 1989a; 1989b), using self-administered questionnaires at baseline, three months, and six months after the baseline. A mixed model for repeated measures conditional growth model analysis was conducted using a group*time interaction as an intervention effect. Results: A total of 841 eligible working mothers participated in this study. For the main pooled analysis, positive relationship with others was significantly improved in the intervention group (pooled effect 0.41 [95% CI 0.08-0.74], t = 2.44, p = 0.015), while the effect size was small (Cohen's d = 0.18). There was no significant effect on autonomy, environmental mastery, personal growth, purpose in life, and self-acceptance. Conclusions: The study demonstrated that the fully automated iACT program was effective in improving PWB in working mothers. However, the effect was small and shown in the limited domain of PWB. Further program improvement is required to achieve a greater effect size and impact on a wider range of PWB.