It takes two: The relative contributions of parent versus child-led regulatory behaviours on toddler vaccination pain.

Background: Past research has established the important role of parent soothing in early childhood pain management. However, limited research has assessed children's own emerging emotion regulation strategies to reduce their pain during vaccination. The purpose of the current study was to understand the relative contributions of child-led emotion-regulation behaviours over and above parent regulatory behaviours and pre-needle distress.

Methods: Toddler-caregiver dyads were videotaped at their 12- and/or 18-month vaccinations. Videos were coded for pain-related behavioural distress, child-led regulatory behaviours (disengagement of attention, parent-focused behaviours, and physical self-soothing), and parent regulatory/soothing behaviours (distraction, physical comfort, rocking, verbal reassurance). Pre-needle distress, followed by parent regulatory behaviours, followed by child regulatory behaviours were used as hierarchical predictors of pain regulation. Two sets of models were estimated at each age, by incorporating parent and child regulatory behaviours at 1 min and 2 min post-needle, separately.

Results: At both ages, child-led parent-focused behaviours predicted less regulation. At 18 months, parent soothing behaviours (e.g. distraction, verbal reassurance, rocking) played a stronger role in regulation, however; the only behaviour that increased regulation was rocking.

Conclusions: Measuring both parent and child regulatory behaviours was important for fully understanding pain-related distress regulation. Toddlers' use of parent-focused regulatory behaviours (e.g. proximity seeking) suggests that they signal to their parent directly when they are struggling to regulate post-needle. The only parent behaviour that supported this regulation was rocking at 18 months, suggesting a greater need to understand the sensitivity of parent behaviours post-needle.

Significance: To our knowledge, this is the first study to examine both parent and child regulatory behaviours following vaccination at different stages in toddlerhood. This investigation allows a deeper understanding of the dyadic nature of early childhood vaccination, as well as the evolving role of the parent through toddlerhood. Importantly, findings suggest that toddlers do not simply wait for their parents to respond to their pain post-needle and provide clear signals to show their need of support in regulation.