PHILADELPHIA — Autism-specific screening conducted at critical intervals is more effective in the early identification of autism than is using a general developmental instrument as a first-line screening technique, Dr. Susan E. Levy said at the annual meeting of the Society for Developmental and Behavioral Pediatrics.
In an investigation of 152 children aged 15–30 months, a general pediatric developmental screening tool did not adequately examine certain “red flag” characteristics or behaviors of autism that are included in autism-specific screening tools, she said.
For example, some of these red flags include when children do not babble or point, do not make meaningful gestures by age 1 year, have poor eye contact, or are losing language or social skills.
Dr. Levy, of Children's Hospital of Philadelphia, and her colleagues at the University of Pennsylvania School of Nursing, Philadelphia, compared the effectiveness of a general screening tool, the Parents' Evaluation of Developmental Status (PEDS), to an autism-specific tool, the Modified Checklist for Autism in Toddlers (M-CHAT), in screening for autism spectrum disorders in the primary care setting.
The study involved administering a general developmental screening tool first, and then an autism-specific screening of children who failed the general developmental screening tool.
The researchers enrolled 152 children with a mean age of 21 months at the Children's Hospital of Philadelphia urban pediatric primary care center and first administered the PEDS and then the M-CHAT instruments.
The results were then analyzed taking into account the two screening strategies.
The PEDS found that in 75% of the children, parents had nonsignificant concerns or no developmental or behavioral concerns.
Parents reported one or more concerns for 25% of the children. In contrast, about 14% of children in the sample scored as at risk for autism spectrum disorders through the M-CHAT, and 86% were considered not at risk.
Of the 114 children who did not have significant concerns after the PEDS, 98 (86%) passed the M-CHAT and 16 (14%) were scored as at risk for autism spectrum disorders after the M-CHAT screening tool.
Of the 38 children who had concerns noted with the PEDS, 32 (84%) passed the M-CHAT and 6 (16%) were scored as at risk with the M-CHAT.
“Children who screen negative for general developmental concerns may score positive on the M-CHAT and vice versa,” Dr. Levy said.
In this study, the Parents' Evaluation of Developmental Status screening tool did not appear to be a good substitute for the M-CHAT when screening specifically for autism spectrum disorders in a general pediatric practice in an urban setting, Dr. Levy said.
Instead, the data seems to support using an autism-specific screening tool for all children at critical ages (18 months, 24 months, and 30 months).
The children who score as having concerns on the Parents' Evaluation of Developmental Status but not on the M-CHAT may be at risk for other delays or disabilities.
These interim results are part of an ongoing study conducted by the Pennsylvania Center for Autism and Developmental Disability and Research and Epidemiology (PA-CADDRE), which is funded by the Centers for Disease Control and Prevention.
The Pennsylvania site is one of six centers around the country collaborating on projects to establish the prevalence, etiology, and risk factors of children with autism spectrum disorders, Dr. Levy said at the meeting.