Assessing cross-national invariance of the Community Assessment of Psychic Experiences (CAPE).

BACKGROUND: The Community Assessment of Psychic Experiences (CAPE) is a 42-item self-report questionnaire that has been developed and validated to measure the dimensions of psychosis in the general population. The CAPE has a three-factor structure with dimensions of positive, negative and depression. Assessing the cross-national equivalence of a questionnaire is an essential prerequisite before pooling data from different countries. In this study, our aim was to investigate the measurement invariance of the CAPE across different countries. METHODS: Data were drawn from the European Union Gene-Environment Interaction (EU-GEI) study. Participants (incident cases of psychotic disorder, controls and siblings of cases) were recruited in Brazil, France, Italy, the Netherlands, Spain and UK. To analyse the measurement invariance across these samples, we tested configural invariance (i.e. identical structures of the factors), metric invariance (i.e. equivalence of the factor loadings) and scalar invariance (i.e. equivalence of the thresholds) of the three CAPE dimensions using multigroup categorical confirmatory factor analysis methods. RESULTS: The configural invariance model fits well, providing evidence for identical factorial structure across countries. In comparison with the configural model invariance, the fit indices were very similar in the metric and scalar invariance models, indicating that factor loadings and thresholds did not differ across the six countries. CONCLUSION: We found that, across six countries, the CAPE showed equivalent factorial structure, factor loadings and thresholds. Thus, differences observed in scores between individuals from different countries should be considered as reflecting different levels of psychosis.

Breastfeeding, Polyunsaturated Fatty Acid Levels in Colostrum and Child Intelligence Quotient at Age 5-6 Years.

OBJECTIVE: To examine the relationship of polyunsaturated fatty acid (PUFA) in breast milk with children's IQ. STUDY DESIGN: In the French Etude des Déterminants pré- et postnatals précoces du développement et de la santé de l'Enfant (EDEN) mother-child cohort, colostrum samples were collected at the maternity unit. Colostrum omega-6 and omega-3 PUFA were analyzed by gas chromatography. At age 5-6 years, the IQs of 1080 children were assessed using the Wechsler Preschool and Primary Scale of Intelligence-III. The relationships of breastfeeding duration and PUFA levels with children's IQs were examined by linear regression. RESULTS: Full scale IQ of ever breastfed children was 4.5 (95% CI: 2.7, 6.2) higher than never breastfed children in the unadjusted model, but this was not statistically significant in the adjusted model (1.3 points higher [-0.4, 3.0]). Any breastfeeding duration was associated with full scale (0.20 [0.00, 0.41] points/month) and verbal (0.31 [0.09, 0.52]) IQ. Colostrum linoleic acid (LA) levels were negatively associated with Verbal IQ (-0.6 [-1.1, 0.0] points per 1% level increase). Children exposed to colostrum high in LA and low in docosahexaenoic acid (DHA) had lower IQs than those exposed to colostrum high in DHA (3.0 [0.5, 5.5] points) and those exposed to colostrum low in LA and DHA (4.4 [1.6, 7.3] points). Finally, the association between breastfeeding duration and child IQ was stronger when LA levels were high. CONCLUSIONS: Duration of breastfeeding and colostrum PUFA levels were associated with children's IQs in the EDEN cohort. These data support breastfeeding and add evidence for the role of early PUFA exposure on childhood cognition.