title: Impairment measures versus inflammatory RODS in GBS and CIDP: a responsiveness comparison.
abstract: This study aimed to 'define responder' through the concept of minimum clinically important differences using the individually obtained standard errors (MCID-SE) and a heuristic 'external criterion' responsiveness method in patients with Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). One hundred and fourteen newly diagnosed or relapsing patients (GBS: 55, CIDP: 59) were serially examined (1-year follow-up). The inflammatory Rasch-built overall disability scale (I-RODS), Rasch-transformed MRC sum score (RT-MRC), and Rasch-transformed modified-INCAT-sensory scale (RT-mISS) were assessed. Being-a-responder was defined as having a MCID-SE cut-off ≥1.96. Also, the correlations between patients' scores on each scale and the EuroQoL health-status 'thermometer' (external criterion) were determined (higher correlation indicated better responsiveness). In both diseases, the SEs showed a characteristic 'U'-shaped dynamic pattern across each scales' continuum. The number of patients showing a meaningful change were higher for the I-RODS > RT-MRC > RT-mISS and were in GBS higher than CIDP patients. The MCID-SE concept using Rasch-transformed data demonstrated an individual pattern of 'being-a-responder' in patients with immune-mediated neuropathies, and the findings were validated by the external criterion responsiveness method. The I-RODS showed greater responsiveness compared with the MRC and INCAT-sensory scales, and its use is therefore recommended in future trials in GBS and CIDP.
authors.affiliation: Department of Clinical Genetics, University Medical Centre Maastricht, Maastricht, The Netherlands.
authors.forename: Els K
authors.initials: EK
authors.lastname: Vanhoutte
authors.affiliation: Department of Neurology, University Medical Centre Maastricht, Maastricht, The Netherlands.
authors.forename: Thomas H P
authors.initials: TH
authors.lastname: Draak
authors.affiliation: Department of Neurology, St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, MA, USA.
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Gorson
authors.affiliation: Department of Neurology, Erasmus Medical Centre Rotterdam, Rotterdam, The Netherlands.
authors.forename: Sonja I
authors.initials: SI
authors.lastname: van Nes
authors.affiliation: Department of Neurology, University Medical Centre Maastricht, Maastricht, The Netherlands.
authors.forename: Janneke G J
authors.initials: JG
authors.lastname: Hoeijmakers
authors.affiliation: Department of Neurology, Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: W-Ludo
authors.initials: WL
authors.lastname: Van der Pol
authors.affiliation: Department of Neurology, Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Nicolette C
authors.initials: NC
authors.lastname: Notermans
authors.affiliation: Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Lewis
authors.affiliation: Department of Neurological Sciences, Humanitas Clinical Institute, Milan University, Milan, Italy.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Nobile-Orazio
authors.affiliation: Department of Neurology, Hôpital de la Salpêtrière, Paris, France.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Léger
authors.affiliation: Department of Neurology, Catholique University of Louvain, Leuven, Belgium.
authors.forename: Peter Y K
authors.initials: PY
authors.lastname: Van den Bergh
authors.affiliation: Neuromuscular Diseases Unit, National Neurological Institute "Carlo Besta", Milan, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Lauria
authors.affiliation: Department of Neurology, Toronto General Hospital, Toronto, Canada.
authors.forename: Vera
authors.initials: V
authors.lastname: Bril
authors.affiliation: Department of Neurology, Toronto General Hospital, Toronto, Canada.
authors.forename: Hans
authors.initials: H
authors.lastname: Katzberg
authors.affiliation: Department of Neurology, Centre for Neuromuscular Disease, National Hospital for Neurology and Neurosurgery, London, UK.
authors.forename: Michael P T
authors.initials: MP
authors.lastname: Lunn
authors.affiliation: Department of Neurology, Centre de Référence des Maladies Neuromusculaires et de la SLA, Hôpital de La Timone, Marseille, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Pouget
authors.affiliation: Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Anneke J
authors.initials: AJ
authors.lastname: van der Kooi
authors.affiliation: Department of Neurology, London Health Science Center, London, Canada.
authors.forename: Angelika F
authors.initials: AF
authors.lastname: Hahn
authors.affiliation: Department of Neurology, Erasmus Medical Centre Rotterdam, Rotterdam, The Netherlands.
authors.forename: Pieter A
authors.initials: PA
authors.lastname: van Doorn
authors.affiliation: Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Cornblath
authors.affiliation: Department of Neurology, Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Leonard H
authors.initials: LH
authors.lastname: van den Berg
authors.affiliation: Department of Neurology, University Medical Centre Maastricht, Maastricht, The Netherlands.
authors.forename: Catharina G
authors.initials: CG
authors.lastname: Faber
authors.affiliation: Department of Neurology, University Medical Centre Maastricht, Maastricht, The Netherlands.|Department of Neurology, Spaarne Hospital, Hoofddorp, The Netherlands.
authors.forename: Ingemar S J
authors.initials: IS
authors.lastname: Merkies
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004185:Disability Evaluation; D005260:Female; D020275:Guillain-Barre Syndrome / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D007155:Immunologic Factors; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D020277:Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / Q000175:diagnosis / Q000503:physiopathology*; D012677:Sensation / Q000502:physiology*; D055815:Young Adult
chemical_list: D007155:Immunologic Factors
keywords: Rasch; immune-mediated neuropathies; minimum clinically important difference; outcome measure