Uncertainty clouds take a look at of ‘preemptive’ remedy to ease autism traits | Spectrum
Early days: Researchers say preventive autism intervention has strong benefits, but some question the data.
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This week’s headlines hailed behavioral therapy parents can offer their babies to reduce the intensity of children’s autism characteristics and reduce their chances of being diagnosed by the age of 3, but independent experts urge caution: the effects observed were low, and analysis of the study begs the question of whether the results can withstand replication.
“Even given the sub-optimal statistical analysis and sub-ideal results, this is important, relevant and timely work,” says April Benasich, professor of developmental cognitive neuroscience at Rutgers University in Newark, New Jersey involved in the research.
The study is a follow-up to a 2019 single-blind randomized controlled trial of 103 babies who showed behavioral signs of autism between the ages of 9-14 months. Six months later, babies who received experimental therapy fared no differently from controls for autism traits.
In the new job, the same team followed 89 of the children up to 3 years of age. By then, 12 children had been diagnosed with autism, and those in the control group who hadn’t received experimental therapy were three times more likely than those who had to meet diagnostic criteria for the condition, the study shows. The work appeared in JAMA Pediatrics on Monday.
“Although the extent of these effects was quite small and of uncertain clinical significance,” says Benasich, “it is still worthwhile and, above all, teaches parents valuable skills in communicating with their children.”
The children in the study all tested positive for signs of autism between 9-14 months of age and 9-14 months of age on the social attention and communication monitoring measure. The tool is most accurate when given multiple times, but many children only take it once before or not being referred to a specialist, says lead researcher Andrew Whitehouse, a professor of autism research at Telethon Kids Institute in Western Australia.
The parents of 50 babies learned to perform the experimental therapy called iBASIS-Video Interaction to Promote Positive Parenting (iBASIS-VIPP). In 10 bi-weekly sessions, parents watched videos of their own interactions with their child while a trained therapist gave them communication tips. During the original five-month study period, the parents practiced their skills with their children for at least 15 minutes a day. The parents of another 53 children received no education, but some received other therapies elsewhere.
The new work assessed autism characteristics in 44 children in the control group and 45 children in the treatment group aged 2 and 3 years using the Autism Diagnostic Observation Schedule (ADOS). Clinicians also examined the children for autism at 3 years of age.
Those whose parents had completed an education showed less pronounced autism characteristics than the controls when measured over a period of 12 months to 3 years. And three children in the treatment group were diagnosed with autism compared to nine controls.
“The children who fell below the diagnostic threshold still had developmental difficulties,” says Whitehouse. “However, this study showed that by working with each child’s unique differences, rather than counteracting them, iBASIS VIPP Therapy was effective in helping their early childhood development.”
The results are consistent with studies of the same therapy in younger siblings of autistic children – so-called “babysibs”, who are about 20 times more likely to develop autism than the general population. After training their parents with iBASIS-VIPP, baby siblings showed significant reductions in autism characteristics by the age of 3, as measured by ADOS or the Autism Observation Scale for Infants, a 2017 study.
The primary endpoint of the study, differences in feature severity, was statistically significant according to a one-sided test that only looked at whether a treatment was more effective than the control condition. But choosing a one-tailed test instead of a more rigorous two-tailed test – which explains the possibility that a treatment is either more or less effective than usual treatment – increased the likelihood that the results would be statistically significant. says Benasich.
“This analytical choice precludes the possibility of examining an effect in the other direction, and given the weak statistical results at the one-sided level, there is a likelihood that the two-sided results would or would not reach significance,” says Benasich.
Diagnosing autism at 3 years of age, the secondary outcome of the study, met traditional statistical significance thresholds for two-tailed testing, although a pre-registered plan for conducting the study required a one-tailed test, says Whitehouse.
The small number of participants also reduces confidence in the results, says Regina Nuzzo, senior advisor on statistical communications at the American Statistical Association, which was not involved in the study.
Regardless of the statistics, the research represents a “very rare” example of a research team doing everything in their power to evaluate an early autism intervention with minimal risk of bias, says Kristen Bottema-Beutel, associate professor of teaching, Curriculum and Society at Boston College in Massachusetts who was not involved in the work.
“They ticked all the boxes that researchers never tick,” she says. For example, the team pre-registered their hypotheses and detailed how they randomized the groups.
But the study’s premise – what Bottema-Beutel calls preventive intervention to keep people from becoming autistic – raises ethical concerns, she says. “Many autistic traits are just differences; they’re not necessarily something that makes it harder for you to reach developmental milestones.”
The team is sensitive to these concerns, says Whitehouse. “Our focus on supporting parent-child interaction is to support and enrich the social environment around the baby – and thus create learning opportunities for the baby that are tailored to the child’s unique abilities.”
He and his colleagues plan to continue tracking the children to see if the effects found in the study are permanent.