The objective of this study was to derive a factor structure of the measures of the National Institutes of Health (NIH) Toolbox Cognition Battery (CB) that is representative of cognitive abilities in a large ethnically diverse cohort of 8-year-old children in Aotearoa New Zealand.

Our sample comprised of 4298 8-year-old children from the Growing Up in New Zealand study. We conducted exploratory and confirmatory factor analysis for the NIH Toolbox CB measures to discover the best-fitting factor structure in our sample. Measurement invariance of the identified model was tested across child’s gender, socio-economic status (SES), and ethnicity.

A three-dimensional factor structure was identified, with one factor of Crystallised Cognition (Reading and Vocabulary), and two distinguished factors of fluid cognition: Fluid Cognition I (Attention/Inhibitory Control, Processing Speed, and Cognitive Flexibility) and Fluid Cognition II (Working Memory, Episodic Memory). The results demonstrate excellent model fit, but reliability of the factors was low. Measurement invariance was confirmed for child’s gender. We found configural, but neither metric nor scalar, invariance across SES and the four major ethnic groups: European, Māori, Pacific Peoples, and Asian.

Our findings show that, at the age of 8 years, fluid abilities are more strongly associated with one another than with crystallised abilities and that fluid abilities need to be further differentiated. This dimensional structure allows for comparisons across child’s gender, but evaluations across SES and ethnicity within the Aotearoa New Zealand context must be conducted with caution. We recommend using raw scores of the individual NIH Toolbox CB measures in future research.

To simulate effects of different scenarios of folic acid fortification of food on dietary folate equivalents (DFE) intake in an ethnically diverse sample of pregnant women.

A forty-four-item FFQ was used to evaluate dietary intake of the population. DFE intakes were estimated for different scenarios of food fortification with folic acid: (i) voluntary fortification; (ii) increased voluntary fortification; (iii) simulated bread mandatory fortification; and (iv) simulated grains-and-rice mandatory fortification.

Ethnically and socio-economically diverse cohort of pregnant women in New Zealand.

Pregnant women (n 5664) whose children were born in 2009–2010.

Participants identified their ethnicity as European (56·0 %), Asian (14·2 %), Māori (13·2 %), Pacific (12·8 %) or Others (3·8 %). Bread, breakfast cereals and yeast spread were main food sources of DFE in the two voluntary fortification scenarios. However, for Asian women, green leafy vegetables, bread and breakfast cereals were main contributors of DFE in these scenarios. In descending order, proportions of different ethnic groups in the lowest tertile of DFE intake for the four fortification scenarios were: Asian (39–60 %), Others (41–44 %), European (31–37 %), Pacific (23–26 %) and Māori (23–27 %). In comparisons within each ethnic group across scenarios of food fortification with folic acid, differences were observed only with DFE intake higher in the simulated grains-and-rice mandatory fortification v. other scenarios.

If grain and rice fortification with folic acid was mandatory in New Zealand, DFE intakes would be more evenly distributed among pregnant women of different ethnicities, potentially reducing ethnic group differences in risk of lower folate intakes.

To evaluate the sociodemographic and lifestyle factors associated with insufficient and excessive use of folic acid supplements (FAS) among pregnant women.

A pregnancy cohort to which multinomial logistic regression models were applied to identify factors associated with duration and dose of FAS use.

The Growing Up in New Zealand child study, which enrolled pregnant women whose children were born in 2009–2010.

Pregnant women (n 6822) enrolled into a nationally generalizable cohort.

Ninety-two per cent of pregnant women were not taking FAS according to the national recommendation (4 weeks before until 12 weeks after conception), with 69 % taking insufficient FAS and 57 % extending FAS use past 13 weeks’ gestation. The factors associated with extended use differed from those associated with insufficient use. Consistent with published literature, the relative risks of insufficient use were increased for younger women, those with less education, of non-European ethnicities, unemployed, who smoked cigarettes, whose pregnancy was unplanned or who had older children, or were living in more deprived households. In contrast, the relative risks of extended use were increased for women of higher socio-economic status or for whom this was their first pregnancy and decreased for women of Pacific v. European ethnicity.

In New Zealand, current use of FAS during pregnancy potentially exposes pregnant women and their unborn children to too little or too much folic acid. Further policy development is necessary to reduce current socio-economic inequities in the use of FAS.