Repeatability of maternal report on prenatal, perinatal and early postnatal factors: findings from the IDEFICS parental questionnaire

Objective: To investigate the repeatability of maternal self-reported prenatal, perinatal and early postnatal factors within the IDEFICS (Identification and prevention of dietary-and lifestyle-induced health effects in children and infants) study. Design: Data are from the baseline survey of the longitudinal cohort study IDEFICS in eight European countries. Subjects: A total of 420 parents from eight countries (43-61 per country) were asked to complete the parental questionnaire (PQ) twice at least 1 month apart. Measurements: The PQ assesses prenatal (maternal weight gain), perinatal (child's birth weight and length, Caesarean (C)-section, week of delivery) and early postnatal factors (exclusive breastfeeding, breastfeeding, introduction of solid food). Intra-class correlation coefficients (ICCs) were calculated to compare maternal reports on prenatal, perinatal and early postnatal factors between the first and second PQ. Results: In total, 249 data sets were considered for the analyses. Overall, maternal reports for prenatal and perinatal factors showed higher repeatability (ICC = 0.81-1.00, P <= 0.05 for all) than those for early infant nutrition (ICC = 0.33-0.88, P <= 0.05 for all). Perfect agreement was found for parental reports on C-section (ICCall = 1.00, P <= 0.05). There was stronger agreement for duration of breastfeeding (ICC = 0.71, P <= 0.05) compared with exclusive breastfeeding (ICC = 0.33, P <= 0.05). Maternal reports showed moderate correlation for the introduction of several types of food (cereals ICC = 0.64, P <= 0.05; fruits ICC = 0.70, P <= 0.05; meat ICC = 0.83, P <= 0.05; vegetables ICC = 0.75, P <= 0.05), and high correlation (ICC = 0.88, P <= 0.05) for cow's milk. Conclusion: Maternal reports on pregnancy and birth were highly reproducible, but parental recall of early infant nutrition was weaker and should be interpreted more cautiously. International Journal of Obesity (2011) 35, S52-S60; doi:10.1038/ijo.2011.35