Parent-mediated social communication therapy for young children with autism (PACT): long-term follow-up of a randomised controlled trial

Abstract

SummaryBackgroundIt is not known whether early intervention can improve long-term autism symptom outcomes. We aimed to follow-up the Preschool Autism Communication Trial (PACT), to investigate whether the PACT intervention had a long-term effect on autism symptoms and continued effects on parent and child social interaction.MethodsPACT was a randomised controlled trial of a parent-mediated social communication intervention for children aged 2–4 years with core autism. Follow-up ascertainment was done at three specialised clinical services centres in the UK (London, Manchester, and Newcastle) at a median of 5·75 years (IQR 5·42–5·92) from the original trial endpoint. The main blinded outcomes were the comparative severity score (CSS) from the Autism Diagnostic Observation Schedule (ADOS), the Dyadic Communication Assessment Measure (DCMA) of the proportion of child initiatiations when interacting with the parent, and an expressive-receptive language composite. All analyses followed the intention-to-treat principle. PACT is registered with the ISRCTN registry, number ISRCTN58133827.Findings121 (80%) of the 152 trial participants (59 [77%] of 77 assigned to PACT intervention vs 62 [83%] of 75 assigned to treatment as usual) were traced and consented to be assessed between July, 2013, and September, 2014. Mean age at follow-up was 10·5 years (SD 0·8). Group difference in favour of the PACT intervention based on ADOS CSS of log-odds effect size (ES) was 0·64 (95% CI 0·07 to 1·20) at treatment endpoint and ES 0·70 (95% CI −0·05 to 1·47) at follow-up, giving an overall reduction in symptom severity over the course of the whole trial and follow-up period (ES 0·55, 95% CI 0·14 to 0·91, p=0·004). Group difference in DCMA child initiations at follow-up showed a Cohen's d ES of 0·29 (95% CI −0.02 to 0.57) and was significant over the course of the study (ES 0·33, 95% CI 0·11 to 0·57, p=0·004). There were no group differences in the language composite at follow-up (ES 0·15, 95% CI −0·23 to 0·53).InterpretationThe results are the first to show long-term symptom reduction after a randomised controlled trial of early intervention in autism spectrum disorder. They support the clinical value of the PACT intervention and have implications for developmental theory.FundingMedical Research Council.

Low‐dose suramin in autism spectrum disorder: a small, phase I/II, randomized clinical trial

“…This has occurred historically for two counterbalancing reasons: (1) because it is generally believed that ADOS scores are diagnostic and are not sensitive to change once the diagnosis is established, and (2) because training effects have the potential to produce improvements that are artifactual. With regard to the first point, under the right circumstances ADOS scores can be sensitive to change and have recently been used successfully as an outcome measure in a large autism treatment study 47. With regard to the second point, if training effects occurred, they were asymmetric, since improvements were only observed in the suramin treatment group and were not observed in the placebo group (Table 4).…”

International multicentre randomised controlled trial of improvisational music therapy for children with autism spectrum disorder: TIME-A study

“…Recent findings from a trial of parent-mediated communication-focused therapy failed to find clear evidence of effectiveness at 1 year, 22 but did so at 5 years. 37 We cannot rule out the possibility that there could have been differences in outcomes for children over a longer period. However, a further difference from that study is that the involvement of parents allows for generalisation across situations, and the music therapy as delivered in this trial did not consistently involve parents in a way that transferred skills.…”

“…35,36 The ADOS was originally developed as a diagnostic tool to assess whether or not children have impairments and unusual behaviours that would indicate ASD. Although some previous studies have used the ADOS to assess the clinical effectiveness of interventions, 22,37,38 concerns have been raised about the suitability of the ADOS to assess changes in the adaptive functioning of children with ASD. 39 Similar limitations apply to the SRS as an outcome measure for measurement of skill development in young children.…”

Childhood autism: The good, the bad and the ugly

“…The authors went on to say that future studies need to examine the long-term effects of these early interventions on affected children's development. The second study, documented in 2016, clearly showed that in a long-term follow-up of a randomised controlled trial on parent-mediated social communication therapy for young children with autism (PACT) study, on children 2 to 4 years old with core autism, the results were the first to show long-term symptom reduction after early intervention in autism spectrum disorder 5 . The data supported the clinical value of the PACT intervention and the outcomes have implications for management of affected children.…”