Page 32 - Sample Moderate prematurity, socioeconomic status, and neurodevelopment in early childhood

Chapter 3
Measures and procedure
Behavioural and emotional problems were measured using the Child Behavior Checklist (CBCL) for ages 1.5-5.21, 22 The CBCL 1.5-5 has good psychometric properties and is widely used in diverse service settings and in research.22 The reliability and validity of the problem scales have been confirmed for the Dutch version of the CBCL.23, 24 It consists of 99 problem items and one open-ended item for writing down other problems, not listed on the form. Each item can be rated by the parent as follows: 0, not true; 1, somewhat or sometimes true; or 2, very true or often true. We computed seven syndrome scales by summing the ratings for the items that comprise each syndrome. Subsequently, problem scores were subdivided in three categories: normal range (<93th percentile); subclinical or borderline range (93rd to 97th percentile); and clinical or elevated range (>97th percentile). Furthermore, two broad-band groups, internalizing and externalizing problems, and the total problems score were computed. For these scores cut-offs for subclinical and clinical problems were set at the 84th and 90th percentiles, following the CBCL manual.21 Internalizing problems consist of syndrome scales for emotionally reactive behaviour, anxious/depressed behaviour, somatic complaints, and withdrawn behaviour. Externalizing problems consist of syndrome scales for attention problems and aggressive behaviour.
Data on background characteristics were collected by a general parental questionnaire that was sent to the parents simultaneously with the CBCL. The questionnaire consisted of questions about medical conditions of the mother during pregnancy, delivery, developmental and medical conditions of the child, family composition, and socioeconomic status. Furthermore, for all children, retrospective data files from PCH centres, paediatricians, midwives, and obstetricians were available. In this way, it was possible to check some important variables such as gestational age and birth weight in more than two data files. When contradictions were found, these were checked by information in discharge letters.
Analysis
We compared behavioural and emotional problems as measured by the CBCL for MP and term-born children at pre-school age. First, characteristics (i.e., small for gestational age, gender, age of the child at completing the CBCL, family composition, number of siblings, maternal age, educational level, and ethnicity) between MP and term-born children were compared using chi-square tests.
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