Lessons and opportunities from autism screening in high-risk children.

As we expand population screening of autism spectrum disorders (ASD), it is increasingly apparent that the social and communication problems of ASD identified by current tests are also present in other disabilities. Moore et al. report that an alarming 41% of 2-year-old extremely preterm infants screened positive for autism using the Modified Checklist of Autism in Toddlers (M-CHAT), with a decrease to the still high rate of 16% when using more stringent scoring criteria of this test. Another striking finding was a positive screen rate of 99.5% in those children with motor, vision, or hearing impairment. This picture highlights the conundrum we now face in screening for autism in high-risk populations. Are we truly identifying children with ASD or are we, instead, screening for a wide range of overlapping disorders with the common features of delayed social, non-verbal, and verbal communication skills? In another study of preterm children with similar results, those with other impairments had more failed items as the severity of impairment rose, with four of the test’s six critical items commonly present. While these items are predictive of ASD, the studies highlight the problems in the predictive validity of the M-CHAT. Questions arise when we ask parents of a child with impaired motor, sensory, or cognitive skills about the child’s ability to point, bring objects, imitate, respond to name, or direct gaze. The child with cerebral palsy may be unable to point or imitate movement or to bring a toy to a parent. The child with hearing impairment may not respond typically to name. Those with cognitive impairment may have limited imitation skills. Research on the early signs of ASD has fostered improved recognition and increased public and professional awareness of its symptoms. New screening instruments have been developed for earlier recognition in clinical populations, with the M-CHAT most widely recommended and used. While the M-CHAT is described as a screening test specific for autism, the findings in the Moore et al. and Luyster et al. studies highlight its foundation in early non-verbal and verbal language development. These skills are prime areas of disability in ASD, but are not unique to it. Several important observations and lessons emerge from investigation of ASD screening in preterm and other high-risk populations, and from other studies of early development. We are acquiring a better general understanding of the development of social interaction and related language skills in early childhood and its critical nature. The Moore et al. study also highlights the need for recognition and further investigation of the interrelatedness of the development of these skills with the development of sensory, motor, and cognitive skills. While exercising caution in the interpretation of the results of current ASD screens, we should recognize these positive screens as the beginning of the process of disability identification. The low positive predictive value of current screening tools demands further in-depth evaluation following a positive screen, using the M-CHAT recommended follow-up interview or further diagnostic testing, especially when used in children at highrisk for other neurodevelopmental disorders. We have also made progress in the treatment of ASD through early intensive behavioral and developmental interventions, with improvements seen in cognitive performance, language, and adaptive behavior skills. These methods may also prove beneficial to children with other disabilities, particularly when there are delays in cognitive, social, or language development. The focus on autism during the past decade has opened our eyes to the importance of early language development and related social functioning. As we perform developmental surveillance and screening in the preterm child and others, we must be sure to use this knowledge to advance a child’s development in these areas. We must take the lessons learned in autism screening and turn them into new opportunities for identification and treatment of the communication disabilities, both for children with ASD and those with other disabilities.