Effectiveness of a blended online behavioral parent training program for Vietnamese parents of children with ADHD: A randomized controlled trial with 3‐month follow‐up

Abstract Background Behavioral parent training (BPT) is an evidence‐based intervention for children with attention‐deficit/hyperactivity disorder (ADHD); however, evidence from low‐ and middle‐income Asian countries remains scarce. This randomized controlled trial evaluated a culturally adapted blended BPT program for Vietnamese parents of elementary school‐aged children with ADHD. Methods Eighty‐six parents of children (6–11 years) with a clinician‐confirmed DSM‐5 diagnosis of ADHD were randomized to a blended BPT program ( n = 43) or treatment as usual plus psychoeducational materials ( n = 43). The intervention comprised six weekly 2‐h online group sessions, each followed within the same week by a 1‐h individual home‐based support session, and 12 weekly support telephone calls across a 3‐month maintenance period. Parenting skills (Parenting Skills Assessment Scale), parent‐rated child ADHD symptoms (Vanderbilt ADHD Diagnostic Parent Rating Scale), and parenting stress were assessed at baseline (T1), post‐intervention (T2), and 3‐month follow‐up (T3). The analyses included 80 participants with complete data (intervention, n = 37; control, n = 43). Results Parenting skills improved substantially in the intervention group relative to the control group (group × time interaction: F (2, 156) = 20.75, p < .001, partial η 2 = 0.21; baseline‐adjusted between‐group d = 1.28 at follow‐up). Parent‐rated ADHD symptoms decreased significantly within the intervention group (T1→T3: −4.14 points, p < .001), but the baseline‐adjusted between‐group differences were small and not statistically significant (T2: p = .057; T3: p = .075; adjusted d ≈ 0.28–0.30). Parenting stress declined similarly in both groups. Exploratory mediation analyses indicated a significant indirect effect on follow‐up ADHD symptoms through improved parenting skills ( ab = −1.86, 95% bootstrap CI [−4.01, −0.37]). Conclusion The culturally adapted blended BPT program was feasible and produced large, sustained improvements in parenting skills among Vietnamese parents. The effects on parent‐rated ADHD symptoms were small and require confirmation in adequately powered trials. Trial registration Thai Clinical Trials Registry, TCTR20260212003 (retrospectively registered on February 12, 2026). Registration number: TCTR20260212003. Available at: https://www.thaiclinicaltrials.org/show/TCTR20260212003 .