The Early Life Exposures Assessment Tool (ELEAT) for Autism Spectrum Disorders

Background:  Little is known about the non-genetic, potentially modifiable causes of autism spectrum disorders (ASD) and progress is hindered by the lack of standardized, valid, reliable and inexpensive instruments for assessing the role of candidate environmental exposures.

Objectives:  We propose to expand the evaluation of environmental factors in the context of ASD by developing a validated instrument, the Early Life Exposure Assessment Tool (ELEAT), which can be used to assess environment in studies of autism.

Methods: We are in the process of developing, refining, validating, and testing the reliability and feasibility of a self-administered questionnaire to be completed by parents with respect to health and environmental exposures in time windows that are relevant to ASD.

Results:  We systematically reviewed the literature to identify ASD-relevant exposure domains with the potential for reliable and valid assessment in a self-administered parent survey.  We selected items corresponding to these domains, with preference given to previously validated items, and grouped them into modules – diet / lifestyle, home environment, and maternal conditions / medical interventions - that can be used together or separately.  The questionnaire will be piloted on participants in the MARBLES study, and responses will be compared with data previously collected prospectively during gestation to assess the reliability of retrospective recall.  Criterion and construct validity will be based on comparing questionnaire items responses to corresponding environmental measures, biological measures, and medical record data in the SUPERB, MARBLES, and CHARGE studies, respectively.  Feasibility-testing of the ELEAT will be conducted in families of the CHARGE and AGRE studies.

Conclusions: With this instrument comes the potential to achieve enhanced sample sizes through administration of standardized instrument modules to broader populations and data pooling.  Such a strategy will allow for assessment of relatively rare gestational exposures and interaction effects, including gene-environment interaction.  In addition, the open-source availability of this instrument should facilitate collection and sharing of environmental exposure data among ASD investigators working with diverse populations using dissimilar study designs, enabling collaborations that would not otherwise have had the resources and/or expertise for such exploration.  As a result, the number of ASD studies able to assess environmental influences of neurodevelopmental compromise would be greatly expanded, bringing us closer to understanding the potentially modifiable environmental contributions to ASD etiology and paving the way to improved prevention and treatment strategies.