Validation of claims-based diagnoses in individuals with neuromyelitis optica spectrum disorder


  • A chart review-based validation study found that the single International Classification of Diseases, 9th revision (ICD-9-CM) code for neuromyelitis optica (NMO) is inaccurate for the identification of individuals with the disease.

Why this matters

    The diagnosis of NMO/neuromyelitis optica spectrum disorder (NMOSD) is rare and therefore it is difficult to study individuals through large randomized-controlled trials. This study aimed to validate the ICD-9-CM code for effective use in retrospective chart reviews of large healthcare databases.