Development of a new scale for dysphagia in patients with progressive neuromuscular diseases: the Neuromuscular Disease Swallowing Status Scale (NdSSS)

Ayako Wada, Michiyuki Kawakami, Meigen Liu, Eri Otaka, Atsuko Nishimura, Fumio Liu, Tomoyoshi Otsuka

Research output: Contribution to journalArticle

19 Citations (Scopus)


Dysphagia is one of the most critical problems in patients with progressive neuromuscular diseases. However, clinically useful and practical scales to evaluate dysphagia are limited. Therefore, the aim of this study was to develop such a scale. An 8-stage Neuromuscular Disease Swallowing Status Scale (NdSSS) was developed and tested for its inter- and intrarater reliabilities, concurrent validity, and responsiveness. The NdSSS was used to evaluate 134 patients with Duchenne muscular dystrophy (DMD) and 84 patients with amyotrophic lateral sclerosis (ALS). Inter- and intrarater reliabilities were examined with weighted kappa statistics. Concurrent validity was assessed by correlating the NdSSS with the existing scales [Functional Oral Intake Scale (FOIS), Functional Intake LEVEL Scales (FILS), and ALS Functional Rating Scale-Revised Swallow (ALSFRS-R Sw)], using Spearman’s correlation coefficients. Responsiveness was determined with the standardized response mean (SRM). For inter- and intrarater reliabilities, the weighted kappas were 0.95 and 1.00, respectively, for DMD; and 0.98 and 0.98, respectively, for ALS. The NdSSS showed strong correlations with the FOIS (rs = 0.87 for DMD, rs = 0.93 for ALS, p 

Original languageEnglish
Pages (from-to)2225-2231
Number of pages7
JournalJournal of Neurology
Issue number10
Publication statusPublished - 2015 Oct 1



  • Amyotrophic lateral sclerosis
  • Instrument
  • Muscular dystrophy
  • Psychometric properties
  • Swallowing disorders

ASJC Scopus subject areas

  • Clinical Neurology
  • Neurology

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