Investigating convergence of cardiac and behavioral indicators of distress during routine vaccinations over the second year of life.

There is considerable variability regarding the convergence between behavioral and biological aspects of distress responses in toddlerhood, and little research has investigated the convergence of these measures in high distress. The aim of the current study was to describe patterns of distress responses to vaccinations as indexed by both pain-related behavioral distress and heart rate (HR) at 12 and 18 months. Caregiver-toddler dyads were part of an ongoing longitudinal cohort observed during 12- (N = 158) and 18-month (N = 122) well-baby vaccinations. Parallel-process growth mixture models discerned two distinct groups at 12 months and three distinct groups at 18 months. All groups had comparable pain-related behavioral distress and HR responses post-vaccination, with most participants displaying high arousal and regulation to baseline levels following the vaccination. However, at 18 months, an important minority had a blunted response or did not regulate to a low level of distress by 3 min post-needle. Post hoc analyses revealed that higher baseline pain-related behavioral distress predicted membership in the majority groups at 12 and 18 months. These results highlight the developmental differences and variability in behavioral and cardiac indicators of distress regulation across the second year of life.

An examination of the reciprocal and concurrent relations between behavioral and cardiac indicators of acute pain in toddlerhood.

The aim of this study was to examine the concurrent and predictive relations between healthy toddlers' pain behavior and cardiac indicators (ie, heart rate [HR] and respiratory sinus arrhythmia [RSA]) during routine vaccinations. Caregiver-infant dyads were part of a longitudinal cohort observed during their 12- and 18-month vaccinations. Behavioral and cardiac data were simultaneously collected for 1-minute preneedle and 3-minutes postneedle. Videotapes were coded for pain behaviors (FLACC; Merkel et al., 1997), and cardiac data were analyzed (HR, RSA) during sequential 30-second epochs. Four separate cross-lagged path models were estimated using data from the 12- (n = 147) and 18-month (n = 122) vaccinations. Across 12- and 18-month vaccinations, predictive within-measure relations were consistent for FLACC, HR, and RSA, reflecting good stability of these pain indicators. Behavioral indicators predicted subsequent HR and RSA within the immediate postneedle period. Both baseline behavior and HR/RSA predicted future pain scores. Concurrent residual relations between behavioral and cardiac indicators were inconsistent across time and indicators. Results suggest that behavioral and cardiac indicators reflect unique aspects of the nociceptive response. As such, multimodal assessment tools should be used and contextualized by child age, cardiac indicator, baseline behavior/physiology, and pain phase.

Parental Report of Self and Child Worry During Acute Pain: A Critical Factor in Determining Parental Pain Judgment.

OBJECTIVE: The objective of this study was to determine which variables predict parental postvaccination pain ratings. It was hypothesized that after child behavior, parental sensitivity, and parental reports of worry would be the strongest predictors. METHODS: Data for 215 parent-child dyads were analyzed from a longitudinal cohort at the preschool (4 to 5 y of age) vaccination. Preschoolers' pain behaviors 15 seconds, 1 minute 15 seconds, and 2 minutes 15 seconds after the painful immunization were observed and rated. Parental sensitivity, as well as parental own worry and their assessment of their child's worry, were assessed before and after the needle. Three regression models were used to determine the impact of these variables on parental pain assessment. RESULTS: Preschoolers' pain behaviors moderately accounted for variance in parental pain judgment (R=0.23 to 0.28). Parental sensitivity was not a significant unique predictor of parental pain rating at the preschool age. Parental assessment of their own worry and worry about their preschoolers after the needle were critical contributors to parental pain judgment. Post hoc analyses suggest that parents who report low child worry, are more congruent with their child during regulatory phases postvaccination. However, both parents with high and low self-worry had more congruent pain ratings with child pain behavior scores during the reactivity phase. DISCUSSION: The study suggests that the majority of variance in parent pain ratings was not predominantly based on preschoolers' pain behaviors. Parental worry levels and their assessment of their child's worry were also significant predictors. Clinical implications are discussed.

Infant Clinical Pain Assessment: Core Behavioral Cues.

Diverse behavioral cues have been proposed to be useful cues in infant pain assessment, but there is a paucity of evidence on the basis of formal psychometric evaluation to establish their validity for this purpose. We aimed to examine 2 widely used coding systems, the Neonatal Facial Coding System (NFCS) and the Modified Behavior Pain Scale (MBPS), by examining their factor structures with confirmatory factor analysis using a large archival data set. The results indicated that an item-reduced NFCS scale with 3 items produced a 1-factor pain model that maintained the good psychometric properties of the 7-item scale. In addition, it was found that MBPS also has challenging internal consistency, with items that are weakly correlated as well as highly redundant. One item of the MBPS may be able to capture the construct of pain equally well or potentially improve its psychometric properties. Redefinition of the MBPS with cry as a sole indicator was suggested. This analysis provides 2 new iterations of the NFCS and MBPS that improve construct validity and internal consistency. These shorter versions also improve the feasibility of both measures and increase their potential for clinical use because less time is required for their administration. PERSPECTIVE: This article presents new iterations of the NFCS and MBPS scales. These revised measures improve the internal consistency of the measures, feasibility of use of the tools in research settings, and the efficiency of the coding process. The revised tools could also improve the feasibility of coding within clinical settings.

Preschool Needle Pain Responding: Establishing 'Normal'.

The current study sets forth to provide descriptive data for preschool vaccination pain responding as well as examine longitudinal relationships over early childhood. Growth mixture modeling was first used to describe stable subgroups of preschoolers on the basis of their pain response patterns over 2-minutes post-needle. Secondly, a parallel-process growth curve model was used to assess the stability of acute pain responding from 12 months of age to preschool age. Specifically, we examined whether preschool pain-related distress or regulation could be predicted from 12-month acute pain responding. Preschool participants were part of a Canadian longitudinal cohort (The Opportunities to Understand Childhood Hurt [OUCH] cohort; N = 302). Growth mixture modeling analyses discerned 3 distinct groups of preschoolers, with an important minority not regulating to low-no pain by 2 minutes post-needle. There were no significant associations between 12-month and preschool pain responding. These results highlight the steep trajectory of development between these different stages of early childhood and the variability of pain responding at the preschool vaccination. PERSPECTIVE: This study provides descriptive data for preschool vaccination pain responding as well as examines longitudinal relationships over early childhood. Demonstrating significantly different pain patterns from infancy, 25% of preschoolers are displaying suboptimal regulation trajectories. This considerable minority poses a significant concern because of the established trajectory of phobia onset in middle childhood.