Page 23 - Sample Moderate prematurity, socioeconomic status, and neurodevelopment in early childhood

Information on the percentage of children having abnormal ASQ scores is given in Table 2, for all children together, and for low SES and MP children separately. Of the 1470 participating children 6.8% had a total development score two standard deviations below the mean of the Dutch reference group. For low SES and MP children these percentages were 11.0% and 8.3%, respectively.
Table 2 Overview of abnormal scores on the Ages and Stages Questionnairea for all children together, and 2 for low SES and moderately preterm-born children separately
Total Score
Fine Motor Gross Motor Communication Problem-Solving Personal-Social
6.8 (96/1416) 6.4 (93/1458) 5.1 (74/1450) 8.3 (119/1436) 5.3 (76/1444) 4.6 (67/1455)
11.0 (27/245) 8.2 (21/256) 5.5 (14/256) 9.2 (23/251)
10.0 (25/251) 7.4 (19/257)
8.3 (74/891) 8.1 (74/917) 5.7 (52/911) 9.5 (86/906) 6.1 (55/908) 5.7 (52/915)
Developmental outcomes: risks multiply
ASQ Domains
All children
n=1470 % (n)
Low SESb
n=260
% (n)
Moderately preterm
n=926
% (n)
Abbreviations: SES, socioeconomic status; ASQ, Ages and Stages Questionnaire
a Abnormal score on the ASQ: scores two standard deviations or more below the mean score of the Dutch reference group.
b Low SES: one standard deviation or more below the mean of the standardized SES.
In Table 3 we present three models of multivariate logistic regression analyses, using standardized values for SES and GA. The highest values of SES and GA served as reference. Odds ratios represent the effect of a one standard deviation decrease in SES or GA. In multivariate Model 1, we assessed separate effects of SES and GA, with mutual adjustment. Decreasing SES was associated with an increased risk of delay in overall development, fine motor, communication, problem-solving, and personal-social skills. Decreasing GA was associated with an increased risk of delay in overall development, fine motor and communication skills. In Model 2 we analyzed synergistic effects of SES and GA (SES*GA). No statistically significant interaction effects were found, except for communication skills. This indicates that the joint effects of SES and GA on communication skills are less than multiplicative. For the other domains and for overall developmental delay, the effects of SES and GA are multiplicative, as is the case for any logistic model without interactions. In the final and adjusted Model, decreasing SES and decreasing GA were both associated with an increased risk of delay in overall development and delay in the domains fine motor, communication, and personal-social. Only decreasing SES significantly increased the risk of problem-solving skills. Lastly, we found no relationship of decreasing SES or GA with delay in gross motor skills.
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