Validation of the Modified Checklist for Autism in Toddlers, Revised with Follow-up in a Population Sample of 30-Month-Old Children in Iceland: A Prospective Approach.

Researchers tested an autism screening checklist (M-CHAT-R/F) with 1,585 children at 30 months old in Iceland. The tool correctly identified about 6 out of 10 autistic children and rarely gave false alarms (99% accuracy for non-autistic children). Most importantly, children identified through screening were diagnosed 10 months earlier than those missed by the screening. While the tool doesn't catch every autistic child, it helps many families get earlier diagnosis and support.

This prospective validation study examined the Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) in a population sample of 1,585 30-month-old children in Iceland. Children were screened during routine well-child visits and followed for at least 2 years to identify autism diagnoses. The screening tool demonstrated moderate sensitivity (62%) and high specificity (99%), with positive and negative predictive values of 72% and 99% respectively. Importantly, children correctly identified through screening received autism diagnoses approximately 10 months earlier than those missed by the screening.

Despite suboptimal sensitivity, the tool contributed to earlier diagnosis for many children, supporting its integration into well-child care programs.

M-CHAT-R/F shows promise for integration into routine well-child care despite suboptimal sensitivity. The tool's high specificity and contribution to earlier diagnosis support its clinical utility. However, negative screening results should not rule out autism concerns, and clinical judgment remains important.

The study only reports basic psychometric properties without detailed analysis of factors affecting screening accuracy. The 62% sensitivity indicates significant missed cases. Follow-up period details and comprehensive diagnostic procedures are not fully described in the abstract.

The Modified Checklist for Autism in Toddlers, Revised with Follow-up was validated on a population sample in Reykjavik, Iceland. The participants (N = 1585) were screened in well-child care at age 30 months and followed up for at least 2 years to identify autism cases. The sensitivity, specificity, positive and negative predictive values were 0.62, 0.99, 0.72, and 0.99, respectively. True-positive children were diagnosed 10 months earlier than false-negative children.

Autism symptom severity and the proportions of children with verbal and performance IQs/DQs < 70 were similar between groups. Although the sensitivity was suboptimal, the screening contributed to lowering the age at diagnosis for many children. Adding autism-specific screening to the well-child care program should be considered.