ASD (autism spectrum disorder) is described as a range of complex neuro-developmental delays characterized by marked impairment in social and communicative functioning with repetitive or restrictive behaviors and interests. Just as with other medical conditions, medical records review is important in diagnosing and treating autism and related disorders. In the United States, prevalence of ASD is estimated at 1 in 68 i.e. 14.7 per 1000 children, with a male to female ratio of approximately 4 to 1, according to the Centers for Disease Control and Prevention’s Autism Developmental Disabilities Monitoring Network (ADDMN). In most US states, the average age of diagnosis is approximately 4 to 5 years though the signs and symptoms of ASD can be detected as early as a child’s first birthday. The best prognoses for ASD are found among children with an early diagnosis and subsequent early intensive behavioural intervention, experts say.
With regard to autism, the challenge the medical community has is how to reliably diagnose a condition in children for which no objective tests are available. Physicians rely on the clinical presentation and historical report of parents at primary care visits. A 2-stage developmental screening tool, the Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) has been endorsed for use by the American Academy of Pediatrics. It is a 20-item questionnaire that parents complete during a routine toddler check-up; either at the 18-month check-up or the 24-month one.
When administered and scored appropriately, this tool is considered to be reliable and sufficiently sensitive. However, improper use of the new follow-up interview questions, improper scoring, and parental misunderstanding of questions have been shown to considerably jeopardize the positive predictive value of this screening tool.
- Problems arise when the healthcare providers conduct their own improvised interview instead of administering the standardized, algorithmic follow-up interview questionnaire, assuming that the child seems fine and that the parent possibly misinterpreted one or more of the questions.
- Providers who review the answers with parents without adhering to the follow-up interview often make the screening process subjective. This results in reduced accuracy and reliability of the M-CHAT-R/F.
- Practices already struggling to implement the meaningful use of EMRs will also have to develop a workflow/interface that allow results from the M-CHAT-R/F follow-up interview which may have been collected and recorded via an online tool to be downloaded, scanned and entered into a patient’s medical record.
Recent news highlighted in www.spectrumnews.org drew attention to the fact that the vast majority of children flagged for autism on this widely used screening tool are never diagnosed with the condition. This is according to an unpublished medical records review of more than 13,500 children. Some children who are not flagged are diagnosed with autism several years later, which is a matter of great concern. The M-CHAT flags just 40% of children eventually diagnosed with this condition. Most children who are flagged require a follow-up to determine whether they need an evaluation. Though nearly 90% of the children flagged in the new study needed this follow-up only 43% got it. The reasons could be that clinicians are too busy and toddler check-ups are often too short to include the follow-up. Among the 917 children who screened positive for autism, some after the follow-up and some without a follow-up, 128 were diagnosed with autism by age 4. This shows that the M-CHAT wrongly flagged 86% of children for a follow-up.
This risk of ‘false positives’ had been cited by the U.S. Preventive Services as a reason to withhold support for universal screening in February 2016. False positives were risky because it could lead to wrong diagnoses and families may have to spend time and money on unnecessary therapies.
The predictive value of M-CHAT increases with a child’s age, and it seems to be highest in children older than 2 years. The findings of the study suggest that screening for autism would be more effective at the 24-month check-up than the 18-month one. The M-CHAT may not be foolproof, but it is hoped that if autism screening is performed well, the children with the highest needs will be identified as early as possible.