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Reliability and Validity of a Short Dietary Intake Questionnaire for Retrospective Collection of Nutrients during Gestation in Autism Studies
International Meeting for Autism Research (IMFAR) (2015)
  • R. J. Schmidt, University of California, Davis
  • Adrianne Widaman, University of California, Davis
  • D. E. Deines, Centers for Disease Control and Prevention, National Center for Health Statistics
  • D. J. Tancredi, University of California, Davis
Nutrition needs increase during pregnancy and are critical for brain development. Evidence is
accumulating for a role of gestational nutrition in autism etiology. A new shorter tool for collection of
maternal nutritional intake during pregnancy could facilitate research in this area.
To develop a tool to collect dietary and supplement intake during pregnancy with a focus on
nutritional factors and timing relevant to neurodevelopment and likely to influence autism risk, and
assess the tool’s reliability and validity in a high-risk ASD population.
Candidate nutritional factors were selected based on a thorough literature review. Retrospective
assessments of nutritional intakes during pregnancy were included in the ELEAT (Early Life Exposure
Assessment Tool) during a pilot test conducted with participants from the MARBLES pregnancy cohort
study of high-risk siblings of children with autism. Retrospective responses were compared with
responses to supplement intake questions and/or the previously validated 2005 Block food frequency
questionnaire (FFQ) prospectively collected by MARBLES during a pregnancy at least 2 years
previously. Longer and shorter versions of the ELEAT dietary module were tested. Nutrient values
were calculated for the ELEAT dietary module using reported frequency of intake and nutrient values
for foods from the USDA nutrient database obtained through NDSR. Agreement between
retrospectively assessed food and nutrient intakes and prospectively reported intakes based on
supplement questions and the Block FFQ were evaluated using Kappa coefficients, Spearman Rank
Correlation Coefficients (rs) and Concordance Correlation Coefficients (ccc). Asymptotic 95%
confidence intervals (CIs) for Spearman correlations are based on Fisher’s Z transformation.
Supplement questions in both MARBLES and the ELEAT were completed by 114 women. MARBLES FFQ
dietary intakes were compared among 54 women who completed the ELEAT long form and among 23
who completed the ELEAT short form. Kappas were moderate for most supplements on whether or
not they were taken, but modest for timing. Correlations across most individual food items and
categories were fair to moderate on both the long and short ELEAT modules. Most quantified
nutrient values from the long form of the ELEAT were moderately correlated (rs= 0.3 – 0.5) with those
on the Block FFQ. More nutrients, especially aggregate measures, based on the short ELEAT module
had only modest, weak or even inverse correlations with the FFQ, however primary nutrients of
interest displayed strong correlations: dietary folate equivalents, rs=0.56 (CI: 0.19, 0.79); iron,
rs=0.59 (CI: 0.23, 0.80); fiber, rs=0.52 (CI: 0.14, 0.77).
Responses on the ELEAT long form dietary and supplement modules were moderately reliable overall,
even with recall after several years, and produced nutrient values that were moderately correlated to
previously collected prospective measures. As with all FFQs, the ELEAT dietary module is not meant to
assess exact nutrient intake for each participant, but rather can be used to rank participants on
their responses in terms of food group intake, calcium, iron, folate, potassium, fiber, choline, vitamin
K and vitamin C intake. This short ELEAT dietary module can be added to autism studies to
retrospectively assess maternal nutrient contributions to ASD etiology.
Publication Date
May 15, 2015
Salt Lake City, UT
Presented by R.J. Schmidt.
Citation Information
R. J. Schmidt, Adrianne Widaman, D. E. Deines and D. J. Tancredi. "Reliability and Validity of a Short Dietary Intake Questionnaire for Retrospective Collection of Nutrients during Gestation in Autism Studies" International Meeting for Autism Research (IMFAR) (2015)
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