JMIR Publications

ABSTRACT

Background:

Hospitalized children frequently experience pain and distress. Pain is a multidimensional experience involving both sensory and emotional components, necessitating multimodal management strategies. Socially assistive robots (SARs) have shown promise as non-pharmacological interventions in pediatric care. However, the interaction mechanisms through which SARs influence pain and emotional responses, particularly positive emotion and real-time emotional dynamics during child–robot interaction, remain underexplored.

Objective:

This study, titled the HAPPY (Hospitalized Assistance for Pediatric Pain Yields) study, aimed to evaluate the association between a SAR-based intervention and postoperative pain in hospitalized children and to examine whether different levels of engagement are associated with changes in real-time emotional dynamics.

Methods:

A single-group pretest–posttest design was conducted with 37 hospitalized children (mean age 7.35, SD 2.06 years) following tonsillectomy or adenoidectomy. The intervention was structured into three sequential phases: Phase 1 (warm-up/limited engagement), Phase 2 (educational video/passive engagement), and Phase 3 (social interaction/active engagement). Pain was assessed using the Wong-Baker FACES pain scale and observed behavioral FLACC scales. Emotional response, as valence, was measured using an automated facial expression recognition system (FaceReader 10). Changes in pain were analyzed using Wilcoxon signed-rank tests, and differences in emotional valence across phases were examined using the Friedman test with post hoc pairwise comparisons.

Results:

Self-reported pain significantly decreased from a median of 6 (IQR 4–6) to 4 (IQR 2–4) (P<.001), and observer-rated behavioral pain decreased from a median of 3 (IQR 2–4) to 1 (IQR 1–2) (P<.001). Overall differences in emotional valence across phases did not reach statistical significance (P=.053; Kendall’s W=0.084). However, the V-shaped trajectory of emotional valence was observed, with the lowest values during the passive engagement phase 2 (mean –0.24, SD 0.20) and relatively higher values during the active engagement phase 3 (mean –0.15, SD 0.13). The exploratory post hoc analyses indicated a significant increase in emotional valence from Phase 2 to Phase 3 (adjusted P=.012).

Conclusions:

SAR-based interventions were associated with reductions in postoperative pain in hospitalized children. Although overall emotional differences across phases were not statistically significant, the observed pattern suggests that active engagement may be associated with more positive emotional responses compared to passive engagement. These findings highlight the potential importance of interaction quality in SAR interventions and provide insight into the processes underlying their clinical effects in pediatric care. Clinical Trial: No