Brief report: Follow‐up outcomes of multisystemic therapy for adolescents with an intellectual disability and the relation with parental intellectual disability

Abstract

Research on follow‐up outcomes of systemic interventions for family members with an intellectual disability is scarce. In this study, short‐term and long‐term follow‐up outcomes of multisystemic therapy for adolescents with antisocial or delinquent behaviour and an intellectual disability (MST‐ID) are reported. In addition, the role of parental intellectual disability was examined. Outcomes of 55 families who had received MST‐ID were assessed at the end of treatment and at 6‐month, 12‐month and 18‐month follow‐up. Parental intellectual disability was used as a predictor of treatment outcomes. Missing data were handled using multiple imputation. Rule‐breaking behaviour of adolescents declined during treatment and stabilized until 18 months post‐treatment. The presence or absence of parental intellectual disability did not predict treatment outcomes. This study was the first to report long‐term outcomes of MST‐ID. The intervention achieved similar results in families with and without parents with an intellectual disability.

Family‐systems interventions for families of people with an intellectual disability or who are autistic: a systematic review

“…Three articles (Blankestein et al . 2019, 2020; Wagner et al . 2019) were about adaptations of MST (Henggeler & Schaeffer 2016).…”

“…These MST adaptations were generally well described, and Blankestein et al . (2019, 2020) were the only included studies to report a measure of therapist's adherence to the intervention. However, precisely how some of the adaptations were implemented in practice was unclear.…”

“…2020a,b; Lo & Ma 2022), MST therapists ( n = 2) (Blankestein et al . 2019, 2020; Wagner et al . 2019), non‐systemic therapists ( n = 2) (Marshall & Ferris 2012; McKenzie et al .…”

“…MST is a manualised intervention for adolescents displaying antisocial behaviour, which involves targeting multiple surrounding systems such as family, peers, school and the community. Two articles studied an adapted form of MST for adolescents with an ID (MST-ID) (Blankestein et al 2019(Blankestein et al , 2020, which included training MST therapists about ID and its effect on the family, using more accessible materials and a greater focus on mobilising social support networks. One study evaluated an adaptation for autistic adolescents [MST for youths with autism spectrum disorder (ASD)] (Wagner et al 2019), which involved a focus on the role of interactions between autistic traits and surrounding systems in maintaining disruptive behaviour.…”

“…Marshall & Ferris 2012; Ma et al 2020a, b), systemic therapists (n = 4)(McKenzie et al 2020(McKenzie et al , 2022 Ma et al 2020a,b;, MST therapists (n = 2)(Blankestein et al 2019(Blankestein et al , 2020Wagner et al 2019), non-systemic therapists (n = 2)(Marshall & Ferris 2012;McKenzie et al 2020McKenzie et al , 2022, unspecified therapists (n = 1) and social workers (n = 1)(Ma et al 2020a), but two studies did not report who delivered the interventions.…”