Botulinum toxin for the treatment of oro-facial-lingual-masticatory tardive dyskinesia Academic Article uri icon


  • One of the problems in the assessment of Parkinson's disease (PD) has been the establishment of reliable and valid measures. 1–6 A review of the literature suggests that instruments were sometimes developed for specific situations or purposes and, by default, became widely used over time. This appears to be the case with the Schwab & England scale. 7 This instrument has become a standard assessment tool in PD and has been used and cited in hundreds of research studies and publications. However, the original properties of the measure were never established. 8 In addition to the need for acceptable psychometric properties, it is also important for scales to be used consistently. 3, 4 Interrater reliability is especially important in multicenter clinical trials of new treatments. Statistical analyses are often conducted on evaluations performed by several examiners. Thus, it is …

publication date

  • January 1, 2000