Different stability of social-communication problems and negative demanding behaviour from infancy to toddlerhood in a large Dutch population sample

BACKGROUND Little is known about the stability of behavioural and developmental problems as children develop from infants to toddlers in the general population. Therefore, we investigated behavioural profiles at two time points and determined whether behaviours are stable during early development. METHODS Parents of 4,237 children completed questionnaires with 62 items about externalizing, internalizing, and social-communicative behaviour when the children were 14-15 and 36-37 months old. Factor mixture modelling identified five homogeneous profiles at both time points: three with relatively normal behaviour or with mild/moderate problems, one with clear communication and interaction problems, and another with pronounced negative and demanding behaviour. RESULTS More than 85% of infants with normal behaviour or mild problems at 14-15 months were reported to behave relatively typically as toddlers at 36-37 months. A similar percentage of infants with moderate communication problems outgrew their problems by the time they were toddlers. However, infants with severe problems had mild to severe problems as toddlers, and did not show completely normal behaviour. Improvement over time occurred more often in children with negative and demanding behaviour than in children with communication and interaction problems. The former showed less homotypic continuity than the latter. CONCLUSIONS Negative and demanding behaviour is more often transient and a less specific predictor of problems in toddlerhood than communication and interaction problems.