Parent-reported atypical development in the first year of life and age of autism diagnosis.

The report is retrospective, so parents were recalling early development after diagnosis; recall bias is possible. All children had autism and there was no comparison group without autism, so the study cannot show that early atypical development predicts autism rather than other conditions. Analyses used 406 of 423 children for age when specialist consultation was needed and 396 of 423 for age of diagnosis. The sample was mostly mothers, White, university-educated, and higher income, so findings may not apply to families with different backgrounds or less access to services. Age when parents felt specialist consultation was needed was not the same as age when they actually sought help. Children diagnosed after 6 years were excluded. Ethnicity and parent sex could not be examined because too few participants were in some groups. The study did not measure wait times, professionals seen, or diagnostic pathway, so it cannot explain why more areas were linked with earlier diagnosis.

The paper reports funding from the National Health and Medical Research Council and Victoria University of Wellington. No other conflicts of interest are stated.

Do not treat any first-year atypical behavior as a reliable predictor of autism. Only social and restricted or repetitive signs were linked with earlier diagnosis, and the study had no children without autism, so it cannot show that these signs distinguish autism from typical development.