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Onset patterns in autism: Variation across informants, methods, and timing.

Sally Ozonoff¹, Devon Gangi¹, Elise P Hanzel¹

¹Department of Psychiatry and Behavioral Sciences, MIND Institute, University of California, Davis, Sacramento, CA.

Autism Research : Official Journal of the International Society for Autism Research

|March 11, 2018

Summary

Regressive onset in autism spectrum disorder (ASD) is common, contrary to previous beliefs. Current measurement methods may inaccurately report regression rates, questioning their reliability for diagnosing ASD.

Keywords:

early signs infants regression

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Published on: March 27, 2012

Area of Science:

Developmental Psychology
Neurodevelopmental Disorders
Autism Spectrum Disorder Research

Background:

Previous research indicated low rates of regressive onset in autism spectrum disorder (ASD).
Recent findings suggest regressive onset may be more prevalent and potentially under-reported.
Variations in measurement methods could influence reported rates of regression in ASD.

Purpose of the Study:

To systematically investigate how different measurement methods affect the reported rates of regression in autism spectrum disorder (ASD).
To compare prospective versus retrospective and categorical versus dimensional assessments of symptom onset.
To evaluate the accuracy and agreement of various methods used to measure developmental trajectories in infants.

Main Methods:

Prospective assessment of infants with and without a family history of ASD up to age three.
Collection of symptom onset reports using four measures varying informant, decision type, and timing.
Application of latent class growth models to classify individual developmental trajectories.

Main Results:

A majority of children with ASD showed regressive onset using prospective dimensional ratings (88% examiner, 69% parent).
Retrospective or categorical measures yielded significantly lower regression rates (29-47%).
Low agreement was observed between different measurement methods, highlighting potential inaccuracies.

Conclusions:

Declining developmental trajectories, indicative of regressive onset, are common in children with ASD.
The accuracy of widely used methods for measuring ASD onset is questionable.
Findings challenge the reliability of current measurement tools and suggest a need for revised methodologies.