The St. Hans Rating Scale for extrapyramidal syndromes: reliability and validity

Area of Science:

• Psychiatry
• Neurology
• Clinical Pharmacology

Background:

• Neuroleptic-induced movement disorders, including tardive dyskinesia (TD), are common side effects of antipsychotic medications.
• Accurate and reliable assessment tools are crucial for monitoring these movement disorders.

Purpose of the Study:

• To evaluate the reliability and validity of the St. Hans Rating Scale (SHRS) for assessing neuroleptic-induced hyperkinesia, parkinsonism, akathisia, and dystonia.
• To compare the performance of the SHRS with the Abnormal Involuntary Movement Scale (AIMS).

Main Methods:

• The St. Hans Rating Scale (SHRS) and Abnormal Involuntary Movement Scale (AIMS) were administered by 7 raters with varying experience levels to 30 psychiatric patients with tardive dyskinesia (TD).
• Assessments were conducted three times: live evaluation, and two video-based evaluations two weeks apart.
• Intrarater and interrater reliability, construct validity, and convergent/divergent validity were analyzed.

Main Results:

• Experienced raters achieved high intrarater reliability for SHRS (0.91-0.96 for hyperkinesia, 0.82-0.97 for parkinsonism) and AIMS (0.80-0.84).
• Interrater reliability was also high among experienced raters for SHRS (0.89-0.95 for hyperkinesia, 0.95-0.98 for parkinsonism) and AIMS (0.76-0.85).
• SHRS parkinsonism scale showed high construct validity; convergent validity was found between SHRS hyperkinesia and AIMS.

Conclusions:

• The St. Hans Rating Scale (SHRS) is a reliable and valid instrument for assessing neuroleptic-induced movement disorders, particularly parkinsonism and hyperkinesia, in patients with tardive dyskinesia (TD).
• The scale performs well with experienced raters, supporting its clinical utility.
• The findings support the use of SHRS as a valuable tool in psychiatric and neurological assessments of movement disorders.