Neonatal pain analyzer: development and validation

We developed a pain analyzer (ABC analyzer) to perform automatic acoustic analysis of neonatal crying and to provide an objective estimate of neonatal pain. The ABC analyzer uses a validated pain scale (ABC scale) based on three acoustic parameters: pitch frequency, normalized RMS amplitude, and presence of a characteristic frequency- and amplitude-modulated crying feature, defined as "siren cry". Here we assessed the reliability of the analyzer. We enrolled 57 healthy neonates. Each baby was recorded with a video camera during heel prick. Pain intensity was evaluated using a validated scale [Douleur Aigue du Nouveau-Né (DAN) scale] and the analyzer and the two scores were compared. We found a statistically significant concordance between the DAN score and ABC analyzer score (p < 0.0001). The ABC analyser is a novel approach to cry analysis that should now have its properties carefully evaluated in a series of studies, just as is necessary in the development of any other pain measurement tool.