dc.description | This study examined the relative importance of and developmental changes in biologically-based child variables (child vagal tone and child difficultness) and parental contextual variables (maternal behavior during pain and maternal sensitivity) in the prediction of children's pain behavior during routine immunization. Using a cross-section design, a non-random convenience sample of 60 mother-infant dyads were assessed when infants were approximately 6 (N = 30) or 18 (N = 30) months of age. During the first session, which was carried out at a university psychology department, mothers completed a demographic interview, a maternal report measure of infant difficultness, and a self-report measure of parental stress; infants' resting EKG signals were also recorded. Following this session, maternal sensitivity was rated by a trained observer and children's resting EKG signals were used to calculate a measure of child vagal tone, based on spectral analysis. During the second session, which was carried out at a university-affiliated outpatient health clinic, infants' pain behavior during immunization was video-recorded. Using the recordings, infant state prior to immunization, maternal vocalizations during immunization, and child pain behavior during immunization were rated by blind coders. The results indicated that there were developmental shifts in the factors which best predicted children's pain behavior. At 6 months of age, 44% of the variability in infant pain behavior was predicted by infant difficultness and mothers' vocalizations during immunization. At 18 months of age, 35% of the variability in infant pain behavior was predicted by maternal sensitivity and child vagal tone. Individual differences in children's emotion regulation skills and socialization histories may underlie the pattern of factors which predicted child pain behavior at each age period. | en_US |