The Global Assessment of Severity of Epilepsy (GASE) Scale is a reliable, useful tool for assessing epilepsy severity in children in both research and clinical settings, results of a study published in Epilepsia indicate.
The 7-point rating scale’s validity and reliability have previously been made evident. In this study, researchers evaluated the GASE Scale’s construct validity, reliability, and responsiveness to change in epilepsy severity.
Cindy Jauhrur Chan, of Western University in London, Ontario, Canada, and colleagues used data from the Health-Related Quality of Life in Children with Epilepsy Study (HERQULES) (n=374), in which observations were taken at baseline, 6, 12, and 24 months after epilepsy diagnosis.
Using Spearman’s correlation and intraclass correlation coefficient (ICC) to quantify construct validity and realiability, the researchers found that the GASE Scale was at least moderately correlated (r ≥ 0.30) with several key clinical aspects. It was most strongly correlated with frequency and intensity of seizures and interference of epilepsy drugs with daily activities (r > 0.30). Total variation in GASE Scale scores explained by seven core clinical aspects of epilepsy increased over time (R2 = 28% at baseline to R2 = 70% at 24 months). The researchers observed modest test-retest reliability, and found the scale to be responsive to changes in clinical criteria (standardized response mean range: 0.49–0.68; probability of change range: 0.69–0.75; Guyatt’s responsiveness statistic range: 0.56–0.84). The GASE Scale also showed the ability to discriminate “stable” and “changed” patients according to specific criteria and to a composite score (area under the receiver operating characteristic [ROC] curve range: 0.50–0.67).
Overall, the results provide additional evidence that the GASE Scale is valid, reliable, and responsive to changes in epilepsy severity in children, and should be considered a useful tool in both the research and clinical settings.