Application of the Strengths and Difficulties Questionnaire Added Value Score in evaluating the effectiveness of Functional Family Therapy within local authority social work services

Abstract

Background: As 'Blueprints' evidence-based programmes, such as Functional Family Therapy (FFT), originating from the United States, are increasingly implemented in Social Work services, the importance of assessing their effectiveness in a UK context is crucial. To do this, it is not always practical for services to commission randomised control trials or quasi-experimental control trials. The Strengths and Difficulties Questionnaire (SDQ) Added Value Score has been shown to have utility in the evaluation of intervention programmes by controlling for regression to the mean, attenuation and the shifting nature of most childhood psychopathology. Method: The SDQ Added Value Score was used to assess the effectiveness of FFT in two local authorities in Scotland. One hundred and sixty-four families who had finished FFT completed the Strengths and Difficulties Questionnaire, the Outcome Questionnaire and the Client Outcome Measure at pre-and postintervention. Results: Both parents' and adolescents' average psychosocial distress scores significantly decreased on all measures after FFT and many of the scores postintervention fell to a range equivalent with the general population. Furthermore, calculation of the SDQ Added Value Score indicated that adolescents' mean total difficulties scores were lower following FFT than what would have been expected had this intervention not been received, producing an effect size that compares favourably to other interventions. Conclusions: Functional Family Therapy has been identified as an effective intervention for improving the psychosocial functioning of high-risk adolescents and their families. Key Practitioner Message• Social work services are increasingly implementing evidence-based 'Blueprints US' programmes, such as Functional Family Therapy (FFT), into community settings.• FFT was evaluated using the Strengths and Difficulties Questionnaire Added Value Score in two local authorities in Scotland and produced significant decreases in parents' and referred adolescents' mean psychosocial distress scores.• FFT within a Social Work system has the ability to provide support for adolescents with high levels of clinical difficulties and their families in order to improve family well-being.• The FFT model involves working with the whole family to reduce defensive communication patterns, increase supportive interactions, promote supervision and improve effective discipline by parents.

An International Examination of the Effectiveness of Functional Family Therapy (FFT) in a Danish Community Sample

“…Parent‐reports of the SDQ total score demonstrated a moderate effect size, with externalizing, internalizing, and emotional and conduct problems approaching or at a moderate effect size. This is generally in line with the effect sizes of parent‐reported disruptive behavior problems found in other international studies of FFT ( d = 0.53–0.68; Hartnett et al, ; Marshall et al, ). Adolescent‐reported outcomes of the SDQ found small effect sizes for internalizing and externalizing difficulties, emotional and conduct problems, and total difficulty scores, which is comparable to effect sizes found in Hartnett et al ( d = 0.37; 2016).…”

“…Also, parents generally reported larger and more significant changes than adolescents. This difference reflects earlier findings on evaluations with the SDQ (Marshall, et al, ). The variation could be due to parents ‘and adolescents’ experience of problems in differing contexts (De Los Reyes et al, ), but it could also reflect adolescents’ reluctance to report issues concerning themselves (Marshall et al, ).…”

“…This difference reflects earlier findings on evaluations with the SDQ (Marshall, et al, ). The variation could be due to parents ‘and adolescents’ experience of problems in differing contexts (De Los Reyes et al, ), but it could also reflect adolescents’ reluctance to report issues concerning themselves (Marshall et al, ). Previous research has identified the efficacy of FFT in relation to reducing rates of disruptive behavior problems, psychosocial distress, substance abuse (Waldron & Turner, ), and improving family functioning (Hartnett et al, ).…”

“…Despite evidence of FFT's effectiveness in improving family functioning and youth behavior, two of the aforementioned studies found no significant results regarding changes in peer relationships. Hartnett et al () found no significant decrease in adolescent‐reported total difficulties and Marshall et al () found no significant difference in youth peer problems. However, these studies did not examine FFT in comparison to an active control, thus, findings should be interpreted with this limitation in mind.…”

“…Two studies utilizing pre‐post quasi‐experimental designs found that FFT was associated with improved outcomes for youth and parents. Marshall, Hamilton, and Cairns () examined data from two local community authorities in Scotland that provided the FFT intervention to at‐risk adolescents using a pre‐post design. Of the 164 Scottish families who received treatment, caregivers reported experiencing a significant reduction in total difficulties, symptom distress, interpersonal relations, and social roles scores.…”