The influence of gestational age in the psychometric testing of the Bernese Pain Scale for Neonates

Abstract

BackgroundAssessing pain in neonates is challenging because full-term and preterm neonates of different gestational ages (GAs) have widely varied reactions to pain. We validated the Bernese Pain Scale for Neonates (BPSN) by testing its use among a large sample of neonates that represented all GAs.MethodsIn this prospective multisite validation study, we assessed 154 neonates between 24 2/7 and 41 4/7 weeks GA, based on the results of 1–5 capillary heel sticks in their first 14 days of life. From each heel stick, we produced three video sequences: baseline; heel stick; and, recovery. Five blinded nurses rated neonates’ pain responses according to the BPSN. The underlying factor structure of the BPSN, interrater reliability, concurrent validity with the Premature Infant Pain Profile-Revised (PIPP-R), construct validity, sensitivity and specificity, and the relationship between behavioural and physiological indicators were explored. We considered GA and gender as individual contextual factors.ResultsThe factor analyses resulted in a model where the following behaviours best fit the data: crying; facial expression; and, posture. Pain scores for these behavioural items increased on average more than 1 point during the heel stick phases compared to the baseline and recovery phases (p < 0.001). Among physiological items, heart rate was more sensitive to pain than oxygen saturation. Heart rate averaged 0.646 points higher during the heel stick than the recovery phases (p < 0.001). GA increased along with pain scores: for every additional week of gestation, the average increase of behavioural pain score was 0.063 points (SE = 0.01, t = 5.49); average heart rate increased 0.042 points (SE = 0.01, t = 6.15). Sensitivity and specificity analyses indicated that the cut-off should increase with GA. Modified BPSN showed good concurrent validity with the PIPP-R (r = 0.600–0.758, p < 0.001). Correlations between the modified behavioural subscale and the item heart rate were low (r = 0.102–0.379).ConclusionsThe modified BPSN that includes facial expression, crying, posture, and heart rate is a reliable and valid tool for assessing acute pain in full-term and preterm neonates, but our results suggest that adding different cut-off points for different GA-groups will improve the BPSN’s clinical usefulness.Trial registrationThe study was retrospectively registered in the database of Clinical Trial gov. Study ID-number: NCT 02749461. Registration date: 12 April 2016.

Acute pain measured with the modified Bernese Pain Scale for Neonates is influenced by individual contextual factors

“…Very preterm neonates may show less change in heart rate because they are in a state of constant autonomic arousal caused by repeated painful and stressful procedures, which they often experience during their NICU stay (Gibbins, Stevens, McGrath, et al, 2008; Grunau, Oberlander, Whitfield, Fitzgerald, & Lee, 2001). These findings, as well as the results of our previous study (Schenk et al, 2019), indicate the importance of considering a neonate's GA or PMA in pain assessment. The more premature the neonate, the less pronounced is his or her pain response.…”

“…Our findings supported the modified BPSN’s validity and demonstrated its reliability in a Swiss sample of 154 full‐term and preterm neonates with different GA. Furthermore, our findings showed that the younger the GA, the lower the cut‐off point should be that discriminates between no or low pain and moderate to severe pain (Schenk et al, 2019).…”

“…We analysed the influence of individual contextual factors on the variability in neonates’ pain reaction by conducting linear mixed effects analyses using the statistical program R (R Core Team, 2017) and specifically the R‐package lme4 (Bates, Machler, Bolker, & Walker, 2015). Because the behavioural BPSN sub‐score and the BPSN item heart rate had a low correlation ( r = .102–.379) during the heel stick procedures (Schenk et al, 2019), we analysed the modified BPSN total scale and the behavioural and physiological subscales separately.…”

“…Between January 2016 and January 2017 we consecutively assessed a total of 1,673 neonates for eligibility and finally enrolled 162. A flow chart with reasons for exclusion appears in our previous study (Schenk et al, 2019). Eight neonates were excluded from data analysis for missing or poor-quality video sequences.…”

Identification of Neonatal Infant Pain Assessment Tools as a Possibility of Their Application in Clinical Practice in Croatia: An Integrative Literature Review

“…Therefore, in nonverbal individuals, such as neonates, it is very difficult to distinguish between pain and other reasons that cause certain behavioral or physiologic responses, such as agitation or hunger (Hodgkinson et al, 1994). In fact, in neonatal infants, nonspecific physiologic and behavioral indicators of pain may occur during nonpainful stress experiences, making accurate pain assessment difficult (Hummel & van Dijk, 2006;Schenk et al, 2019).…”