Clinically Significant and Reliable Change: Comparing an Evidence-based Intervention to Usual Care

Objectives Multiple Family Groups (MFG) is an evidence-based behavioral parent training developed with a specific focus on increasing engagement and decreasing treatment barriers for families of children with disruptive behavior problems within high-risk communities. Previous studies have demonstrated the effectiveness of MFG in improving oppositional behavior at the group-level compared to services as usual (SAU). However, information is lacking regarding intervention effectiveness on an individual-level (i.e., clinical significance). Methods The reliable change index and clinical cutoff score method was utilized to determine whether MFG produced clinically meaningful changes compared to SAU for both child- and parent-level outcomes in a sample of 320 youth aged 7 to 11-years-old. Results A significantly greater percentage of children in the MFG group experienced clinically meaningful change in problem behaviors compared to the SAU group, ( p = 0.003, 95% [CI]: 1.610–18.481). A significantly greater number of parents in MFG also demonstrated clinically meaningful change in parental experience of stress compared to SAU, ( p = 0.01, 95% [CI]: 1.255–14.704). Conclusions Findings suggested clinically significant and reliable improvements in child problem behaviors and decreases in parental perceived stress for families in MFG compared to SAU. Nevertheless, analyses demonstrated that both MFG and SAU resulted in few families obtaining clinically significant or reliable change in their functioning. Ongoing assessments and deeper understanding of intervention effect are needed to better service families in need. Both group- and individual-level comparisons should be considered when examining the effects of a treatment as they may provide a nuanced understanding of evidence-based interventions.