Favorable parental perception of behaviour at two years' corrected age in very preterm-born children.

Problems in behavioural and emotional outcome are amongst the long-term sequelae of preterm birth. The exact prevalence and associations with perinatal risk factors are unknown. Minimal research has been performed in pre-school aged children, compared to school age. The primary aim of this study was to determine the prevalence of parent-reported behavioural and emotional problems at the age of two in children born at less than 30 weeks' gestational age and/or birth weight less than 1000 g. The secondary aim was to determine whether perinatal factors were associated with the behavioural and emotional outcome. Perinatal characteristics of 144 preterm-born children from the NeoLiFeS cohort were collected retrospectively. Of these children, 101 parents filled out a Childs Behaviour Checklist (CBCL) at the corrected age of two. The results of the CBCL tests were presented as Z-scores, a Z-score of 0 indicating the mean of behavioural scores in the norm population. A Z-score higher than zero indicates less behavioural problems than average, a negative Z-score indicates more problems. Associations between perinatal risk factors and CBCL-scores were analysed using linear regression analyses. Prevalences of clinically relevant CBCL scores were low, 4%, 2% and 5% for total score, internalizing score or externalizing score, respectively. Being part of a twin was associated with higher internalizing Z-scores, indicating less problems in emotional behaviour. Bronchopulmonary dysplasia was associated with lower Z-scores in total and externalizing behaviour. In conclusion, in our cohort generally very few problems in behavioural and emotional outcome were reported at the age of two.