A new study finds that the strongest predictors of care outcomes in autism may not come from how much care a patient receives.

Rather, the best predictors of whether symptoms would improve were baseline symptom severity, socioeconomic status, parental concerns about the loss of observed developmental milestones, and the presence of ADHD symptoms.

“Interestingly, when therapy intensity … was added to our model, predictive accuracy did not improve,” the study states. “This would seem to offer counter evidence to research proposing a linear relation between duration and intensity of therapy with behavioral improvement.”

Overall, the study set out to map the trajectories of children receiving therapy for autism and related conditions and determine outcome predictors. It used data from 13 clinics operated by the multi-specialty autism therapy provider Cortica in California, Texas, Illinois and New Jersey. The data encompassed intake and outcome results for 1,225 children and their families. All children received therapy.

In total, the study found that 65% of children treated by Cortica, which focuses on tailored, holistic medical and behavioral treatment, showed improvements across several domains, while measures for 35% remained stable or improved little.

Autism severity and parent concerns about development provided the most robust predictors of outcomes. Lower economic status was the “most important” predictor of the group that had stable outcomes or improved little.

“What this suggests is that which has actually been known in the field: the more severe the symptoms, the harder it is to improve off of baseline,” Dr. Neil Hattangadi, CEO of Cortica, told Behavioral Health Business. “I do not think that anyone would look at that and say that it was a surprise. … What our point would be is that this is further evidence that you have to understand and treat all symptoms to help to get these kids to a better place. That part, you think, would be obvious. But it’s not in the sense that most of the field continues to do ABA only without regard to comorbidities.”

The study was led by New York University, the University of California-San Francisco, Boston College and Cortica.

The final model developed using machine learning was able to predict the trajectories of patients based on intake data with 77% percent accuracy. The amount of clinical hours did not improve the model’s accuracy.

“It may in fact be the case, as demonstrated here, that increasing therapeutic hours is not necessarily effective or cost-efficient in improving real-world outcomes for all children,” the study states.

However, relative to previous research, nearly all patients saw at least some improvements from therapy. The 65% improvement cohort demonstrated many improvements across several aspects of adaptive behavior. Between 75% and 91% demonstrated growth according to the Vineland Adaptive Behavior Scales (VABS-3). Other population studies, which are not as well contained within a standardized care model, show that between 70% and 100% of children have stable or regressing outcome trajectories.

“When you personalize therapies, there is less of a dose dependence that you would otherwise see,” Hattangadi said. “It allows you to really personalize the therapeutic program to drive outcomes based on child-specific factors, not therapy hours.”

The comparative newness of ABA relative to other therapies makes the question of setting the correct and appropriate number of therapy hours for each patient something of a controversy. On one hand, proponents of more conventional care models say getting children with autism as much therapy as possible as early as possible will lead to the best and most durable improvements in a child’s life. On the other hand, many look at more recent research and take a realist’s view of ABA within the current payer-provider paradigm and advocate for a more nuanced and lower-hour approach to treatment. In response, high-hour advocates worry about the systemic diminishment of the industry as more forces push down ABA hours.

Still, there are few universal standards for setting the correct amount of clinical hours for any patient. Industry insiders and researchers have taken steps to build parameters to create concrete guidelines for treatment hour recommendations. In one case, some have developed a so-called “calculator” to help establish the right amount of therapy. 

Regardless of clinical efficacy, several payers this year have sought to tamp down on how much they are paying autism therapy providers, especially within Medicaid programs. At the national level, insurance companies have specifically called out ABA as part of what is driving higher-than-expected payments for care.

At the same time, multispecialty autism and pediatric therapy provider organizations are much more common in the space, demonstrating a collective shift from the ABA-centric historical norm that is at least in part driven by investor interest.

In September, Westside Children’s Therapy in Chicago secured private equity backing to expand its multispecialty pediatric therapy model. Earlier in the year, Unison Therapy Services was acquired by Ascend Capital Partners.

Cortica similarly has had success in fundraising for its approach to autism and other neurodivergent conditions. It secured $80 million about a year ago in its latest funding effort.