brand new paper on autism prevalence in NJ in 2002 8-year olds versus 2006 8-year olds
some highlights:
" For 2006, a total of 533 children with autism spectrum disorder were identified, consistent with prevalence of 17.4 per 1000 (95% confidence interval = 15.9–18.9), indicating a significant increase in the autism spectrum disorder prevalence (p < 0.001), between 2002 (10.6 per 1000) and 2006. The rise in autism spectrum disorder was broad, affecting major demographic groups and subtypes. Boys with autism spectrum disorder outnumbered girls by nearly 5:1."
"... contrary to expectation, comparing 2002 and 2006 estimates, we found significant increase in the proportion of children satisfying the criteria for AD but not in children identified with ASD-NOS. Interestingly, 70%–75% of 8-year-old ASD children, across all surveillance cycles, satisfied the strict diagnostic criteria for AD ..."
Meaning the more severe autism is on the rise, the type of autism that they could never ever have missed in the past.
They also checked if this rise could be down to better detection in certain ethnic groups, that were less aware of autism in the past and so fewer kids from those groups were diagnosed in the past. But NOPE. The rate of increase is equal across all ethnic groups.
They also checked if the increase could be due to migration (of certain groups with higher prevalence of autism), but NOPE again
They tried to explain away the massive increase they observed with younger age of diagnosing etc, but nothing could account for the difference.
The only limitation of this study, as stated by the authors, is that it might have MISSED a number of milder cases, those that do not require special educational services: “Only children identified for special education or for clinical (developmental) services came under the purview of our surveillance. Some children with Asperger’s syndrome or high-functioning ASD are educated in general education settings and did not come to the attention of their school district or our study, thereby leading to underestimate ASD prevalence …”
So again those cases that would have been missed in the old days are not included here anyway, so the ‘better diagnosing’ mantra doesn't hold water.
They also observed the male : female ratio to be 5:1 in 2006 cohort: “nearly five times as many boys than girls were affected, representing an absolute level of male ASD prevalence (1 in 35) that is startling” [authors' choice of words]
The baseline: “this study suggests that ASD prevalence may be closer to 2%” and they go on to say that this more closely matches new data from UK and South Korea. With two thirds of that number affected by moderate/severe autism.
http://aut.sagepub.com/content/early/2012/11/27/1362361312463977.abstract?rss=1
some highlights:
" For 2006, a total of 533 children with autism spectrum disorder were identified, consistent with prevalence of 17.4 per 1000 (95% confidence interval = 15.9–18.9), indicating a significant increase in the autism spectrum disorder prevalence (p < 0.001), between 2002 (10.6 per 1000) and 2006. The rise in autism spectrum disorder was broad, affecting major demographic groups and subtypes. Boys with autism spectrum disorder outnumbered girls by nearly 5:1."
"... contrary to expectation, comparing 2002 and 2006 estimates, we found significant increase in the proportion of children satisfying the criteria for AD but not in children identified with ASD-NOS. Interestingly, 70%–75% of 8-year-old ASD children, across all surveillance cycles, satisfied the strict diagnostic criteria for AD ..."
Meaning the more severe autism is on the rise, the type of autism that they could never ever have missed in the past.
They also checked if this rise could be down to better detection in certain ethnic groups, that were less aware of autism in the past and so fewer kids from those groups were diagnosed in the past. But NOPE. The rate of increase is equal across all ethnic groups.
They also checked if the increase could be due to migration (of certain groups with higher prevalence of autism), but NOPE again
They tried to explain away the massive increase they observed with younger age of diagnosing etc, but nothing could account for the difference.
The only limitation of this study, as stated by the authors, is that it might have MISSED a number of milder cases, those that do not require special educational services: “Only children identified for special education or for clinical (developmental) services came under the purview of our surveillance. Some children with Asperger’s syndrome or high-functioning ASD are educated in general education settings and did not come to the attention of their school district or our study, thereby leading to underestimate ASD prevalence …”
So again those cases that would have been missed in the old days are not included here anyway, so the ‘better diagnosing’ mantra doesn't hold water.
They also observed the male : female ratio to be 5:1 in 2006 cohort: “nearly five times as many boys than girls were affected, representing an absolute level of male ASD prevalence (1 in 35) that is startling” [authors' choice of words]
The baseline: “this study suggests that ASD prevalence may be closer to 2%” and they go on to say that this more closely matches new data from UK and South Korea. With two thirds of that number affected by moderate/severe autism.
http://aut.sagepub.com/content/early/2012/11/27/1362361312463977.abstract?rss=1