What's in a Name? Autism, Perhaps

SACRAMENTO, Calif. April 2 -- A child who does not respond to his or her name by age one could have an autism spectrum disorder, although this sign of recognition deficiency may be a red herring.

"Failure to respond to name by age 12 months is highly suggestive of developmental abnormality but does not identify all children at risk for developmental problems," wrote Aparna S. Nadig, Ph.D., of the University of California at Davis, and colleagues.

The failure to respond when called by name isn't universal among children with autism spectrum disorders or other developmental disabilities, but it may be a risk marker for unspecified problems, the authors reported in the April issue of Archives of Pediatric & Adolescent Medicine.

They conducted a prospective, longitudinal study to determine whether a response to a name at 12 months could be used as a simple office-based screen for autism and other forms of developmental delays.

They recruited 55 six-month-olds and 101 12-month-olds who were at risk for autism because they had an older sibling diagnosed with autism, and compared them with 89 six- and 12-month-old controls. The controls were children with normally developing older siblings who had negative scores on the same autism screening and social communication instruments used to diagnose the siblings of at-risk children.

The children were tested while sitting on a parent's lap or in a baby seat. The experimenter gave the child a small toy to play with, then walked behind the child and called out his or her name in a clear voice at normal volume. If the child turned and made eye contact the task ended. If the child did not respond, the experiment was repeated after about three seconds, up to a maximum of three tries.

The primary study outcome measures were scores on the Autism Diagnostic Observation Schedule and Mullen Scales of Early Learning at follow-up.

The authors found that there was trend at age six months for children in the control group to require fewer name calls than children in the at-risk group, but this difference was not statistically significant.

By age 12 months, however, all of the controls responded appropriately when their names were called the first or second time, whereas only 86% of children in the at-risk group responded on the first or second try.

Of the 14% of at-risk children who failed the name-calling task 12 had reached their 24-month outcome visits, and of these, five were diagnosed with an autism spectrum disorder, while four others were found to have other types of developmental delays.

"We found that failure to respond to name at age one year showed very high specificity for 24-month outcomes of autism spectrum disorder specifically (0.89) and for any type of developmental delay (0.94)," the authors wrote. "However, sensitivity was lower (0.50 for autism spectrum disorders; 0.39 for all types of delay). Thus, failure to respond to name at the well-child one-year check-up may be a useful indicator of children who would benefit from a more thorough developmental assessment. It will not, however, identify all children at risk for developmental problems."

They cautioned that clinicians should not rely on an intact response-to-name behavior alone to rule out the possibility of a developmental delay in at-risk children.

"While Nadig et al find that a failure to respond to one's name by 12 months, though highly suggestive of developmental abnormalities, is not sufficiently sensitive or specific to warrant its use as a screening tool by itself," noted David J. Schonfeld, M.D., and Patty Manning-Courtney, M.D., of Cincinnati Children's Hospital Medical Center, in an accompanying editorial. "Other research?has demonstrated that screening in a primary care setting is feasible given currently available instruments."

Dr. Nadig and colleagues noted that it will be necessary to update the sensitivity and specificity estimates when all of the children in their study reach 36-month follow-up, as the current study is based only a total group of 71 children, 10 of whom have been diagnosed with an autism spectrum disorder. They suggested that following the cohort to school age to will help to determine the stability of early diagnoses and assess whether there is a relationship between name response and Asperger's syndrome, which may not be clinically evident at 36 months of age.