Thursday, 3 January 2019
DSM-5 autism is "largely comparable to" to DSM-IV-TR autism
"Merry New Year". Welcome back to Questioning Answers in 2019. So let's continue.
The quote heading this post comes from the findings reported by Lisa Wiggins and colleagues  and their research aiming to "replicate agreement between surveillance status based on DSM-IV-TR criteria and DSM-5 criteria for ASD [autism spectrum disorder]." This authorship group have some interest in the description of autism across the DSMs (Diagnostic and Statistical Manual of Mental Disorders) as a function of their involvement with the United States CDC and their other, quite recent publication, talking about the national US autism prevalence estimates in 8-year olds for 2014 (see here).
As well as arriving at the conclusion that 1 in 59 children aged 8-year old in the United States *might* have autism  (still potentially an underestimate according to other recent figures), their latest prevalence paper also, for the first time, introduced the DSM-5 to the Autism and Developmental Disabilities Monitoring (ADDM) Network. Previously, the DSM-IV was top (diagnostic) dog, but with the publication of the DSM-5 (see here) there was a new sheriff in town. And as the DSM-5 started to be utilised more and more widely in diagnostic circles, so the CDC autism estimating teams had to start taking this into account in their musings...
Wiggins et al relied on data for "8-year-old children who had health and education records reviewed for ASD surveillance in metropolitan Atlanta, GA in the 2012 surveillance year as a part of the Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP)." As per the aims and objectives of the MADDSP - "estimates the number of children with selected developmental disabilities in metropolitan Atlanta" - autism is one of the diagnoses included in the surveillance program. DSM-IV-TR criteria for autism were applied to the health and education records of a cohort of children to see if diagnostic thresholds were met. Importantly too we are told that: "a previous ASD diagnosis was not sufficient evidence to confirm DSM-IV-TR surveillance case status." Alongside: "A DSM-5 coding scheme for ASD surveillance was developed by an independent body of ADDM-affiliated experts and then adapted and refined by a CDC-led clinical workgroup." Application of this DSM-5 coding scheme was similarly used on those education and health records data and results were collected and compared.
"Similar to ADDM data reported for the 2014 surveillance period, we found substantial agreement between DSM-IV-TR and DSM-5 surveillance status of ASD in a sample of records reviewed for the 2012 surveillance period." The figures in a little more detail: "46.0% children met both DSM-IV-TR and DSM-5 surveillance status, 44.0% met neither the DSM-IV-TR nor DSM-5 surveillance status, 4.0% met DSM-IV-TR status, but not DSM-5 status, and 6.0% met DSM-5 status, but not DSM-IV-TR status of ASD." The importance of this data is what the quote heading this post talked about: DSM-5 autism is "largely comparable to" to DSM-IV-TR autism. So when the ADDM eventually makes the transition over to DSM-5 derived autism data only, it means that all those years of DSM-IV diagnosed autism are still very much relevant (and can be used as a comparator) in a historical context.
But... the authors do mention about how some other studies have observed that: "fewer children meet DSM-5 criteria for ASD than DSM-IV-TR criteria for ASD in similar service settings" (see here and see here). This requires quite a bit more investigation; in particular how "record-review surveillance [such as that utilised by Wiggins et al] relies on information contained in surveillance records and does not include an in-person evaluation of the child." As I've indicated in my very critical musings on armchair diagnosis of historical persons (see here for an extreme example), there is absolutely no substitute for talking to and directly observing a person who has been referred for a diagnostic assessment. None. I've also previously suggested that another related label that crops up near to the DSM-5 description of autism - social (pragmatic) communication disorder (SCD) - might also need some research attention too. Indeed, I wonder if the ADDM might eventually start reporting on autism and SCD separately...
 Wiggins L. et al. Comparison of autism spectrum disorder surveillance status based on two different diagnostic schemes: Findings from the Metropolitan Atlanta Developmental Disabilities Surveillance Program, 2012. PLoS ONE. 2018; 13(11): e0208079.
 Baio J. et al. Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years — Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2014. Morbidity and Mortality Weekly Report (MMWR). 2018; 67(6): 1-23.