The purpose of this review was to quantitatively synthesize studies using acceptance and commitment therapy (ACT) with individuals with neurodevelopmental disorders (NNDs), their parents, and staff members that support them. Thirty studies published in peer-reviewed journals between 2006 and 2020 met inclusion criteria. They were reviewed and coded on variables associated with participants’ characteristics, settings, dropouts, design type, ACT procedures and measures, social validity, treatment integrity, and main findings. The What Works Clearinghouse (WWC), the revised Cochrane risk-of-bias tool for randomized trials (RoB2) and the Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) were applied to evaluate the quality of the studies. Results indicated that 20 studies used group designs and 10 studies used single-case designs. Participants with NNDs consisted predominantly of those with autism spectrum disorder, attention deficit hyperactivity disorder, and learning disabilities. Group studies reported process and outcome measures exclusively; whereas, single-case studies also incorporated behavioral/direct measures. Overall, results showed mixed improvements across studies using indirect and direct measures. Lastly, quality assessment for group studies presented moderate or serious risk of bias and two single-case studies did not meet WWC evidence of effectiveness. Directions for future research and practice are discussed.

Cultural stigma, shame, self-concealment, and language and socio-economic barriers often keep Asian immigrant parents and children away from mental and behavioral services in the United States. Research shows that increased levels of parent distress suggest a negative impact on parenting practices and correlate child-maltreatment. Therefore, this study aimed to test one functionally contextual strategy to address such issues. The current study evaluated the effects of an online Acceptance and Commitment Training (ACT) Matrix for Japanese-speaking mothers living the United States. A nonconcurrent multiple baseline single-subject design across four mothers was used to assess the effect of ACT Matrix on value-driven behaviors, parental engagement (session attendance and daily assignment completion), parental distress, and psychological flexibility. The study consisted of a baseline, treatment (three ACT Matrix treatment sessions adapted from the six-step protocol), maintenance, and follow-up phases. A visual analysis reporting level, trend, variability, immediacy of change and overlap was used to identify a functional relation between the treatment and observable overt behaviors of value-driven behaviors and daily assignment completion. In addition, a non-overlap of all pairs was used to measure effect sizes for these behaviors. For psychological flexibility and parental distress, we used the reliable change index to assess whether clinically significant improvement occurred or not. The results revealed that the online ACT Matrix parent training program was effective in improving all four dependent variables. Mothers reported that the training was culturally sensitive, effective, and acceptable. The details of findings and the implications for future research as preventive science are discussed.