This is part of our Autism Aware series that focuses on statistics about autism.
On March 38, the CDC announced an increase in autism prevalence, now at 1 in 68 US children aged eight. It is based on data collected in 2010. We’d like to say this was a surprise, but honestly, we saw it coming. Last year we wrote about another “increase” in the autism prevalence estimate which put the rate at 1 in 50, also announced by the CDC. This rate was based on parent reports, collected via phone interviews of parents of school-aged children in the US. Which sparks our thoughts to go in two directions: parents can report diagnosis earlier than compilation studies and since the data collected in the 1 in 50 study was more recent, diagnosis of autism is increasing.
The announcement by the CDC of 1 in 68 is important, and their evaluation based on 11 ADDM Network sites throughout the US is strong and the methods are good. It’s exactly what we would expect from the CDC. These sorts of evaluations take time and resources, so it makes sense that the numbers are based on diagnostic and evaluation data from four years ago. But we’re going to project that two years from now, the “official” number will be closer to the 1 in 50 rate last year’s parent report study reflects.
You can read the full report here, but there are some rather interesting trends that come out of this report. Trends that point to areas in which we, as parents, can find ways to support one another and also to increase autism awareness. The report states specifically that the increase to 14.7% in eight year olds in 2010 from 11.3% in 2008 is due largely to increased awareness of autism and improvements in diagnostic methods (or more accurately, increased screening). The work we do to increase awareness is having an effect. As is the push from parents who request screenings and advocate for comprehensive assessments. But leaving this public health concern up to parents has its downside, as reflected in the CDC’s report.
Diving deeper into the data clearly shows diagnostic disparities. “Consistent with previous reports from the ADDM Network, findings from the 2010 surveillance year were marked by significant variations in ASD prevalence by geographic area, sex, race/ethnicity, and level of intellectual ability.” While those children with high IQ’s account for the largest diagnostic increase in under diagnosed populations, they remain largely in the white affluent sector of the population. Other populations are being missed. “Non-Hispanic white children were approximately 30% more likely to be identified with ASD than non-Hispanic black children and were almost 50% more likely to be identified with ASD than Hispanic children.”
We know autism, as a disorder, knows no socio-economic boundaries. Yet, affluent white children get diagnosed at a much higher rate than other populations. We can assume that this is due to an unequal distribution of resources to parents that fit this profile. Clearly more outreach and services geared toward autism awareness and access to diagnostic and support services need to be funneled to under served populations. Yet, there is another area of concern reflected in this report.
While awareness has grown around autism and more families are being connected to the supports and services that will transform their lives, the median age of diagnosis still hovers around five years of age (4.4 years old). When all studies point to early diagnosis and intervention as the key to the best developmental outcomes, we need to find ways to drop the median age of diagnosis by two to three years. There is a significant gap between when autism can be reliably diagnosed – 18 months – and the age at which children are being diagnosed. And it is specifically these three years which yield the greatest benefits from intervention.
Those of us dedicated to autism awareness can use this report to funnel our energies into those areas which need the most attention: earlier diagnosis and supporting those underserved populations that are struggling with autism under the radar.