Thematic Structure of Preterm Infant Pain Research: A Topic Modeling Analysis Using Latent Dirichlet Allocation

Preterm infants experience frequent painful procedures in neonatal intensive care units (NICUs), yet the overall thematic structure of this extensive body of research remains unclear and has not been systematically characterized.

Latent Dirichlet Allocation (LDA) topic modeling was applied to 879 English abstracts retrieved from international databases (Web of Science, PubMed, CINAHL, and Embase) and regional databases in September 2024. Term frequency-inverse document frequency weighting was used to identify core keywords, and silhouette coefficients were used to determine the optimal number of topics. Topic labels were validated through expert consultation with experienced NICU nurses.

Five themes were identified: physiological and behavioral pain assessment (13.4%), nursing practice and pain management (26.6%), pain-related stress and neurodevelopment (13.0%), pharmacologic interventions (14.4%), and nonpharmacologic interventions (32.5%). Among the core keywords identified, "Premature Infant Pain Profile" was the most frequently occurring term (n = 569).Implications for Practice and Research: Although preterm pain research encompasses assessment, intervention, and developmental perspectives, studies addressing pain-related neurodevelopment were represented less frequently in the literature (13.0%). Nonpharmacologic interventions (32.5%) and nursing practice and pain management (26.6%) accounted for the largest proportions, underscoring the central role of NICU nurses. In practice, integrating family-centered, evidence-based pain management strategies into routine NICU care is essential. Future research should further examine the long-term developmental impact of repeated pain exposure in preterm infants.