Related Experiment Video
Updated: Aug 9, 2026

An Experimental Paradigm for the Prediction of Post-Operative Pain (PPOP)
Published on: January 27, 2010
Validation of a six-graded faces scale for evaluation of postoperative pain in children
A Bosenberg1, J Thomas, T Lopez
1Department of Anaesthesia, University of Cape Town, South Africa.
Insights
This study validates the six-graded faces pain scale for children aged 4-12 years post-surgery. The scale showed good agreement with nurses' observations, proving effective for pediatric pain assessment.
Area of Science:
- Pediatric Anesthesiology
- Pain Management
- Clinical Assessment
Background:
- Faces pain scales are commonly used for self-report pediatric pain assessment.
- Evaluating the validity of a six-graded faces pain scale post-surgery is crucial.
- Comparing children's self-reported scores with nurses' observational assessments provides a robust validity measure.
Purpose of the Study:
- To evaluate the validity of a six-graded faces pain scale in children aged 4-12 years.
- To compare children's self-reported pain scores with nurses' observational pain assessments.
- To analyze pain scores before and after analgesic administration.
Main Methods:
- 110 children (4-12 years) undergoing inguinal surgery participated.
- Standardized anesthesia with preoperative caudal block was used.
- Pain was assessed hourly for 8 hours using a nurse-assessed scale and a child-reported six-graded faces pain scale.
Main Results:
- A high correlation (tau = 0.76) was observed between the two pain assessment methods.
- Strong agreement was found across different hospital populations and age groups, with weakest correlation in 8-12 year olds.
- Pain scores significantly decreased after analgesics, with the proportion of patients scoring above 2 dropping from 86% to 31%.
Conclusions:
- The six-graded faces pain scale is a valid and useful tool for postoperative pain measurement in children aged 4-12 years.
- The scale demonstrates good concordance with experienced nurses' pain assessments.
- Findings support its use in clinical settings for pediatric pain management.
Background:
The faces pain scales are often used for self-report assessment of paediatric pain. The aim of this study was to evaluate the validity of a six-graded faces pain scale after surgery by comparing the level of agreement between the children's report of faces pain scores and experienced nurses' assessment of pain by observation of behaviour. The faces pain scores before, at and after administration of analgesics were analysed. The study was performed in two South African hospitals, one with a mainly rural population and the other with an urban population.
Methods:
A total of 110 children aged 4-12 years, scheduled for inguinal surgery in the two South African hospitals, were included in the study. The anaesthetic technique was standardized. All patients received a caudal block preoperatively. Postoperative pain assessments were made every hour for 8 h after the caudal block was performed. A designated nurse assessed pain by using a four-graded descriptive scale (no, mild, moderate or severe pain) and thereafter the child reported pain by using the six-graded faces pain scale.
Results:
A high correlation was found between the two methods of assessment (tau = 0.76, P < 0.0001). The correlation between methods was high in both hospital populations and in all age groups. The weakest correlation was found in children aged 8-12 years (tau = 0.56, P < 0.01). Significantly lower faces pain scores were found after administration of analgesics compared with pain rating before analgesics (P < 0.0001). The proportion of patients with pain scores above 2 decreased from 86% to 31% (P < 0.001).
Conclusions:
The findings support this six-graded faces pain scale as a useful and valid instrument for measuring pain in the postoperative period in children aged 4-12 years.

