“Comparison of Global Dystonia Rating Scale and Burke-Fahn-Marsden Dystonia Rating Scale in Assessing Dystonia Severity”

https://pubmed.ncbi.nlm.nih.gov/38094647

This study found that the Global Dystonia Rating Scale (GDRS) and the Burke-Fahn-Marsden Dystonia Rating Scale (BFM) have strong correlation in assessing dystonia severity, but GDRS may be preferable for focal and segmental dystonias, and both scales have challenges in discriminating very mild dystonia from other abnormal movements or normal behavior.