Psychiatry · Medical Literature
School-based organizational skills training for upper elementary students: Subgroup and mediating effects.
Abstract
This study examines for whom and how Organizational Skills Training-Tier 2 (OST-T2, Nissley-Tsiopinis et al., 2024) works for students in grades 3 to 5 with organization, time management, and planning (OTMP) difficulties. The study: (1) investigates subgroup differences for the effect of OST-T2 on student homework and academic performance at post-intervention (about 14 weeks), short-term (about 22 weeks) and long-term follow-up (about 55 weeks); and (2) examines whether improvements in student OTMP skills at 14 weeks mediate the effect of OST-T2 on academic and homework performance at 22 weeks. The study used a cluster-randomized design with 22 schools; 182 students in moderation analyses and 133 in mediation analyses. Subgroup-defining variables were: (a) likely diagnosis of ADHD, (b) caregiver-reported child anxiety, (c) severity of baseline OTMP and homework problems, and (d) family socioeconomic level. Findings suggested that OST-T2 is more effective among children with higher anxiety levels as reported by caregivers. The difference in change scores between the high and low anxiety groups on the caregiver-rated metric of OTMP and homework problems was -0.76 (Cohen's d) at post-treatment (95% CI = -0.12, -1.21, p = .021), -0.66 at 22 weeks (95% CI = -0.08, -1.09, p = .017), and - 0.55 at 55 weeks (95% CI = -0.07, -1.03, p = .026). The analyses generally did not detect subgroup effects based on ADHD diagnostic status and families differing in socioeconomic levels. Results also suggested improvements in OTMP skills in response to OST-T2 are likely to signal downstream impact on student homework performance; estimated average causal mediation effect was -0.66 (95% CI = -1.27, -0.19, p < .001), whereas the average direct effect was only -0.07. Additional longitudinal research with larger samples on predefined subgroups is needed.
Clinical relevance
This study addresses a critical gap in school-based mental health by identifying which elementary-aged students (grades 3–5) derive the greatest benefit from a Tier 2 organizational skills intervention (OST-T2), particularly relevant given the high prevalence of OTMP difficulties in children with ADHD and anxiety. Understanding moderators and mediators of treatment response allows clinicians and school psychologists to personalize intervention selection rather than applying a one-size-fits-all approach. With increasing demand for tiered, evidence-based school interventions, these findings have immediate implications for child psychiatrists, pediatric psychologists, and educators managing neurodevelopmental and anxiety-related academic impairment.
Key findings
1. OST-T2 demonstrated significantly greater effectiveness in children with higher caregiver-reported anxiety levels compared to low-anxiety peers, with a between-group difference in change scores of Cohen's d = -0.76 (95% CI = -0.12 to -1.21, p = .021) on caregiver-rated OTMP and homework problems at post-treatment (~14 weeks). 2. The differential benefit for high-anxiety children was sustained at short-term follow-up (~22 weeks): Cohen's d = -0.66 (95% CI = -0.08 to -1.09, p = .017), and at long-term follow-up (~55 weeks): Cohen's d = -0.55 (95% CI = -0.07 to -1.03, p = .026), indicating durable moderation by anxiety severity. 3. No significant subgroup effects were detected based on ADHD diagnostic status, suggesting OST-T2 efficacy does not differ meaningfully between children with and without a likely ADHD diagnosis. 4. Family socioeconomic level did not emerge as a significant moderator of OST-T2 outcomes, supporting equitable effectiveness across socioeconomic strata. 5. Improvements in OTMP skills at 14 weeks significantly mediated downstream homework performance at 22 weeks; the estimated average causal mediation effect (ACME) was -0.66 (95% CI = -1.27 to -0.19, p < .001), whereas the average direct effect was negligible at -0.07, indicating that skill acquisition is the primary mechanism of action. 6. The cluster-randomized design across 22 schools with 182 students in moderation analyses and 133 in mediation analyses provides moderate-quality evidence, though sample size constraints limit definitive conclusions about smaller subgroup effects.
Practice implications
Clinicians and school psychologists should prioritize OST-T2 referral for upper elementary students (grades 3–5) presenting with OTMP difficulties who also carry elevated anxiety symptom burden, as this subgroup demonstrates the largest and most durable treatment gains through at least one year post-baseline. Because OTMP skill acquisition is the principal mediating mechanism — rather than direct intervention effects on homework performance — fidelity to skill-building components of OST-T2 should be closely monitored and reinforced throughout the ~14-week active treatment phase to maximize downstream academic outcomes. The absence of differential effects by ADHD status or socioeconomic level supports broad, equitable implementation of OST-T2 as a Tier 2 school-based intervention without restricting access based on diagnostic category or family income, pending replication in adequately powered, prospective subgroup-defined trials.