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Published on: April 5, 2019
Automated Pain Assessment in Children Using Electrodermal Activity and Video Data Fusion via Machine Learning
Insights
Objective pain assessment in children is crucial. Combining electrodermal activity (EDA) and facial expressions offers a highly accurate, nonverbal method for evaluating post-operative pain in children, achieving 90.91% accuracy.
Area of Science:
- Biomedical Engineering
- Pain Medicine
- Pediatrics
Background:
- Assessing pain in children, especially nonverbal ones, presents significant challenges.
- Current methods rely heavily on subjective self-reports, which can be unreliable.
- Objective pain metrics are needed to supplement existing assessment techniques.
Purpose of the Study:
- To develop and validate an objective pain assessment metric for children.
- To fuse electrodermal activity (EDA) and video facial expression data for enhanced pain detection.
- To evaluate the efficacy of this multimodal approach in post-operative pediatric patients.
Main Methods:
- Collected electrodermal activity (EDA) and video facial expression data from children post-laparoscopic appendectomy.
- Utilized a weighted maximum likelihood algorithm for feature selection from EDA and facial expression data.
- Developed an automated classification algorithm to distinguish clinically significant pain from non-significant pain.
Main Results:
- Individually, EDA and facial expression data showed above-chance accuracy in predicting pain.
- Fusion of EDA and facial expression data significantly improved pain classification accuracy.
- The combined approach achieved 90.91% accuracy, 100% sensitivity, and 81.82% specificity for clinically significant pain.
Conclusions:
- Multimodal objective pain assessment using EDA and facial expressions is effective in children.
- This approach provides a reliable, nonverbal method for pain evaluation in pediatric post-operative recovery.
- The developed algorithm offers an accurate and objective tool for clinical pain assessment in children.
Objective:
Pain assessment in children continues to challenge clinicians and researchers, as subjective experiences of pain require inference through observable behaviors, both involuntary and deliberate. The presented approach supplements the subjective self-report-based method by fusing electrodermal activity (EDA) recordings with video facial expressions to develop an objective pain assessment metric. Such an approach is specifically important for assessing pain in children who are not capable of providing accurate self-pain reports, requiring nonverbal pain assessment. We demonstrate the performance of our approach using data recorded from children in post-operative recovery following laparoscopic appendectomy. We examined separately and combined the usefulness of EDA and video facial expression data as predictors of children's self-reports of pain following surgery through recovery. Findings indicate that EDA and facial expression data independently provide above chance sensitivities and specificities, but their fusion for classifying clinically significant pain vs. clinically nonsignificant pain achieved substantial improvement, yielding 90.91% accuracy, with 100% sensitivity and 81.82% specificity. The multimodal measures capitalize upon different features of the complex pain response. Thus, this paper presents both evidence for the utility of a weighted maximum likelihood algorithm as a novel feature selection method for EDA and video facial expression data and an accurate and objective automated classification algorithm capable ofdiscriminating clinically significant pain from clinically nonsignificant pain in children.

