Tuesday, February 16, 2016

Autism screening

Albert L. Siu, and the US Preventive Services Task Force (USPSTF).  Screening for Autism Spectrum Disorder in Young Children: US Preventive Services Task Force Recommendation Statement.  JAMA. 2016;315(7):691-696.

Description New US Preventive Services Task Force (USPSTF) recommendation on screening for autism spectrum disorder (ASD) in young children.
Methods The USPSTF reviewed the evidence on the accuracy, benefits, and potential harms of brief, formal screening instruments for ASD administered during routine primary care visits and the benefits and potential harms of early behavioral treatment for young children identified with ASD through screening.
Population This recommendation applies to children aged 18 to 30 months who have not been diagnosed with ASD or developmental delay and for whom no concerns of ASD have been raised by parents, other caregivers, or health care professionals.
Recommendation The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for ASD in young children for whom no concerns of ASD have been raised by their parents or a clinician. (I statement)

In a decision on pediatric care that has dismayed autism advocates and some experts, a federal task force has ruled there is not enough evidence to show that screening all US toddlers for autism is good idea.

That decision contradicts recommendations from the American Academy of Pediatrics (AAP) which say children should be screened for ASD at ages 18 and 24 months, along with regular developmental surveillance.

But in a statement published in JAMA on Feb. 16, the US Preventive Services Task Force (USPSTF) left the decision on whether to screen up to parents and clinicians. The USPSTF also called for more research on whether screening is reliable and if early intervention is effective.

“The current evidence is insufficient to balance the benefits and harms of screening for autism spectrum disorder (ASD) in young children for whom no concerns of ASD have been raised by parents or a clinician,” the USPSTF concluded.

The USPSTF decision applies to children 18 months to 30 months old.

Screenings involve simply asking parents standardized questions about their child’s behaviors, scoring the responses, and then making referrals to other specialists if warranted.

While leaving the choice on whether or not to screen up to parents and clinicians, the task force explained that it is not saying screening is necessarily a bad idea—just that it's not clear that everyone needs it, at least based on available studies...

The task force’s final decision remains controversial. It comes at a time when the prevalence of American children diagnosed with autism has risen has increased by 23% since 2008. According to the US Centers for Disease Control and Prevention, that prevalence was 1 on 150 in 2000.

In four accompanying editorials in JAMA reaction to the decision was split.

“There is ample evidence that justifies the current practice of universal autism screening,” Geraldine Dawson PhD argued in her JAMA editorial. Dawson is director of the Duke Center for Autism and Brain Development at the Duke University School of Medicine “Studies indicate that available screening tools do identify children with ASD who would have been otherwise missed and children who begin intervention at an earlier age have improved outcomes,” she added.

Two psychiatrists suggested in their editorial that the task force’s recommendation could have negative impacts on Medicaid funding for pediatricians who screen toddlers and pre-schoolers for developmental symptoms.

Jeremy Veenstra-VanderWeele MD of the Center for Autism and the Developing Brain at New York Presbyterian Hospital and Kelly McGuire MD of Maine Behavioral Healthcare’s Center for Autism and Developmental Disorders in Portland said the assessments are necessary.

Screening for ASD is needed now “to establish appropriate special education services mandated by the Individuals with Disabilities Education and Improvement Act," they wrote. The task force recommendation may reinforce the current disparity of children from affluent, well-educated families being diagnosed at an earlier age than those from lower income groups, they added.

Taking the opposite position in their JAMA editorial, two pediatricians endorsed the task force’s findings. “Although this recommendation may be disappointing to many people, the USPSTF has appropriately applied its methodology to the question of ASD screening and has fulfilled its charge of applying rigorous analysis to the best available evidence,” they said.  Instead, the focus should be on the task force's “call for more research,” Michael Silverstein MD, MPH of Boston University Medical School’s division of general pediatrics, and Jenny Radesky MD, of University of Michigan School of Medicine.

The task force called for large randomized clinical trials of treatment of children whose screenings identified ASD, compared with controls.

In another JAMA editorial, Craig M. Powell MD, PhD. of the University of Texas Southwestern Medical Center in Dallas, TX said the USPSTF’s recommendation is not the “death knell” for autism screening. He sees it as but a “call to arms’’ for funding more neurological research to find ways to help patients and their families.

The task force also found potential harm should there be false-positive screening results. Those could include the time and expense of the up to 40 hours a week of interventions these children may require.

Nevertheless, neither the task force recommendation nor the editorials questioned whether autism represents a huge public health problem. The lifetime cost of supporting an individual with autism ranges from $1.4 million to $2.4 million, Dawson reported in her editorial.

See http://childnervoussystem.blogspot.com/2015/08/autism-screening-in-asymptomatic.html


  1. The USPSTF reviews topics that focus only on asymptomatic populations and services provided in (or referable from) primary care and makes its recommendations by following a transparent set of methodologic processes. The USPSTF concluded that, “the current evidence is insufficient to assess the balance of benefits and harms of screening for ASD in young children for whom no concerns of ASD have been raised by their parents or a clinician” and has given the recommendation an I grade. The I grade stems from the small size and variable quality of intervention studies and from a lack of direct evidence that screening leads to clinical improvement...

    Some critics of the USPSTF’s decision have argued that accumulating direct evidence that accounts for all the complexities around diagnostic confirmation and engagement with treatment is prohibitively expensive and not feasible. While it is important to recognize the challenges involved with accumulating such evidence, the complexity of a clinical problem is no justification for adjusting the USPSTF’s standards for a positive recommendation.

    Rather, consistent with the intent of an I statement, the current USPSTF report is an opportunity to motivate better, more relevant research. Here, the evolution of the USPSTF’s report on adult depression provides an instructive example of how that can happen. The USPSTF currently endorses depression screening when systems (previously termed “depression care supports”) are in place to ensure accurate diagnosis, effective treatment, and follow-up. In its now archived 2009 statement, the USPSTF had accompanied this endorsement with an explicit recommendation against universal depression screening in the absence of such supports. As with ASD, depression is fraught with issues of diagnostic subjectivity, comorbidities, cultural nuances, and difficulties with engagement. By analyzing the highest level of direct evidence for depression screening, the USPSTF was able to determine a critical set of circumstances under which the practice leads to better outcomes. Today, depression care supports have become so “much more widely available and accepted as part of mental health care," that the USPSTF was able to omit its comment on what to do when these supports are absent. A similar evolution can occur for ASD screening; in fact, the National Institute of Mental Health is currently supporting 5 large-scale studies on early identification of ASD and linkage to services, designed to address overarching questions encompassing universal screening, expedited diagnosis, and engagement with treatment. Such initiatives are a promising step in discerning the direct relationship of ASD screening to clinical outcomes

    Michael Silverstein, Jenny Radesky. Embrace the Complexity. The US Preventive Services Task Force Recommendation on Screening for Autism Spectrum Disorder. JAMA. 2016;315(7):661-662.


  2. By the typical USPSTF definition, people undergoing screening have neither current signs nor symptoms. Confirmatory testing to establish diagnosis follows positive screening. Ideally, with definitive treatment, symptoms of the underlying diagnosis itself never occur. In the classic example, mammography detects a suspicious lesion, biopsy diagnoses ductal carcinoma, and surgery removes the cancer before it can spread.

    Unlike cancer, a child cannot have ASD without having symptoms. It is not a disease that can be detected by x-ray or blood test. Autism spectrum disorder is a neurodevelopmental diagnosis based entirely upon behavioral symptoms. The autism “screening” evaluated by the USPSTF simply means eliciting symptoms in a systematic way prior to referral for definitive evaluation. Perhaps because of this mismatch, their description of the “asymptomatic” group includes children “for whom no concerns of ASD have been raised….” This means, unlike in other areas they have evaluated, the children being “screened” do have symptoms...

    This non-recommendation is most jarring when juxtaposed against the decision that the guideline should not apply to children when the health care professionals have concerns about ASD. These concerns would most likely emerge from eliciting a history of relevant developmental symptoms in some nonsystematic way. Thus, by excluding cases with existing “concerns” from their evaluation, the USPSTF inadvertently favors nonsystematic over systematic assessment of potential ASD symptoms in this age range. This flaw in logic suggests that the USPSTF’s methods are simply not appropriate for measures that elicit symptoms that are already a focus within primary care visits...

    Unfortunately, a system that encourages clinicians to only elicit ASD symptoms when they or the parents have “concerns” naturally reinforces the biases that are already evident in ASD diagnosis. Children from affluent, well-educated families are currently diagnosed at a considerably younger age. This is followed by better access to treatment in already privileged communities. By ignoring the advantages of eliciting symptoms systematically, we would likely be compounding health disparities.

    We hope that the USPSTF statement does not trigger a step backward to later diagnosis, later treatment, and more disparity in services for children with ASD. Clinicians, families, and health care funders should instead recognize that ASD “screening” simply does not fit within the rigid USPSTF box. Early data in single studies suggest that it may someday be possible to detect ASD risk before symptoms emerge, via blood tests or eye tracking. These sorts of measures, which would actually fit the USPSTF definition of screening, are likely still a decade away from clinical implementation. Until then, we hope that pediatricians continue the push for systematic assessment of autism symptoms in young children and avoid relying exclusively on a clinical hunch or parental concern.

    Jeremy Veenstra-VanderWeele, Kelly McGuire. Rigid, Inflexible Approach Results in No Recommendation for Autism Screening. JAMA Psychiatry. Published online February 16, 2016. doi:10.1001/jamapsychiatry.2016.0143