A longitudinal study of infant’s development from zero to two years- Pathways, predictors and prevalences of suspected developmental delays
The current thesis “A longitudinal study of infant’s development from zero to two years”, focuses on prevalences of suspected developmental delays (SDD), developmental pathways and predictors in a Norwegian population-based sample of infants. Further, it investigated clinically relevant differences in ASQ mean scores among 6 months old infants in four Norwegian population based samples.
All nine well-baby clinics in five municipalities in south-east Norway participated in the study. The study used the Ages and Stages Questionnaires (ASQ) to measure child development and covers communication, gross motor, fine motor, problem solving and personal-social skills.
The results showed that the prevalence rates of SDD in infants between 4 to 12 months varied from 5.7 to 7.0 %. Gross motor delays were most common during this period. In general, most infants exhibited relatively stable and positive developmental pathways during the two first years of life. There was more heterogeneity in the communication and gross motor areas. Premature birth, low Apgar scores and male sex increased the risk for less beneficial developmental pathways in several areas. Depressive symptoms in mothers post partum predicted lower scores in the communication area. There were few clinically relevant differences in mean ASQ scores between the four Norwegian population-based samples of six-month-old infants.
The prevalence rates of SDD were lower compared to other international and national studies. In some pathways developmental problems seemed to be temporary. These findings highlights the importance of longitudinal follow-up with repeated measurements in Norwegian well-baby clinics attended by close to 100% of the families with infants 0 to 2 years.