title: International clinimetric evaluation of the MG-QOL15, resulting in slight revision and subsequent validation of the MG-QOL15r.
abstract: The MG-QOL15 is a validated, health-related quality of life (HRQOL) measure for myasthenia gravis (MG). Widespread use of the scale gave us the opportunity to further analyze its clinimetric properties.
  
  
  
  We first performed Rasch analysis on >1,300 15-item Myasthenia Gravis Quality of Life scale (MG-QOL15) completed surveys. Results were discussed during a conference call with specialists and biostatisticians. We decided to revise 3 items and prospectively evaluate the revised scale (MG-QOL15r) using either 3, 4, or 5 responses. Rasch analysis was then performed on >1,300 MG-QOL15r scales.
  
  
  
  The MGQOL15r performed slightly better than the MG-QOL15. The 3-response option MG-QOL15r demonstrated better clinimetric properties than the 4- or 5-option scales. Relative distributions of item and person location estimates showed good coverage of disease severity.
  
  
  
  The MG-QOL15r is now the preferred HRQOL instrument for MG because of improved clinimetrics and ease of use. This revision does not negate previous studies or interpretations of results using the MG-QOL15. Muscle Nerve 54: 1015-1022, 2016.
authors.affiliation: University of Virginia, Department of Neurology, Charlottesville, Virginia, 22908, USA.
authors.forename: Ted M
authors.initials: TM
authors.lastname: Burns
authors.affiliation: University of Rochester, Rochester, New York, USA.
authors.forename: Reza
authors.initials: R
authors.lastname: Sadjadi
authors.affiliation: Hanamaki General Hospital, Hanamaki, Japan.
authors.forename: Kimiaki
authors.initials: K
authors.lastname: Utsugisawa
authors.affiliation: University of Virginia, Department of Neurology, Charlottesville, Virginia, 22908, USA.
authors.forename: Kelly G
authors.initials: KG
authors.lastname: Gwathmey
authors.affiliation: University of Virginia, Department of Neurology, Charlottesville, Virginia, 22908, USA.
authors.forename: Amruta
authors.initials: A
authors.lastname: Joshi
authors.affiliation: University of Virginia, Department of Neurology, Charlottesville, Virginia, 22908, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Jones
authors.affiliation: Toronto General Hospital, Toronto, Canada.
authors.forename: Vera
authors.initials: V
authors.lastname: Bril
authors.affiliation: Toronto General Hospital, Toronto, Canada.
authors.forename: Carolina
authors.initials: C
authors.lastname: Barnett
authors.affiliation: Duke University, Durham, North Carolina, USA.
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Guptill
authors.affiliation: Duke University, Durham, North Carolina, USA.
authors.forename: Donald B
authors.initials: DB
authors.lastname: Sanders
authors.affiliation: Duke University, Durham, North Carolina, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Hobson-Webb
authors.affiliation: Duke University, Durham, North Carolina, USA.
authors.forename: Vern C
authors.initials: VC
authors.lastname: Juel
authors.affiliation: Duke University, Durham, North Carolina, USA.
authors.forename: Janice
authors.initials: J
authors.lastname: Massey
authors.affiliation: Duke University, Durham, North Carolina, USA.
authors.forename: Karissa L
authors.initials: KL
authors.lastname: Gable
authors.affiliation: University at Buffalo, SUNY Buffalo, New York, USA.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Silvestri
authors.affiliation: University at Buffalo, SUNY Buffalo, New York, USA.
authors.forename: Gil
authors.initials: G
authors.lastname: Wolfe
authors.affiliation: University of Alabama, Birmingham, Birmingham, Alabama, USA.
authors.forename: Gary
authors.initials: G
authors.lastname: Cutter
authors.affiliation: Hanamaki General Hospital, Hanamaki, Japan.
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Nagane
authors.affiliation: Neurological Institute, Kyushu University, Fukuoka, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Murai
authors.affiliation: Tokyo Medical University, Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Masuda
authors.affiliation: Institute of Neurological Sciences, Southern General Hospital, Glasgow, Scotland.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Farrugia
authors.affiliation: Institute of Neurological Sciences, Southern General Hospital, Glasgow, Scotland.
authors.forename: Caroline
authors.initials: C
authors.lastname: Carmichael
authors.affiliation: Institut de Myologie, GH Pitié-Salpêtrière, Paris, France.
authors.forename: Simone
authors.initials: S
authors.lastname: Birnbaum
authors.affiliation: Institut de Myologie, GH Pitié-Salpêtrière, Paris, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Hogrel
authors.affiliation: Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shahriar
authors.initials: S
authors.lastname: Nafissi
authors.affiliation: Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Fatehi
authors.affiliation: The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, PRC, China.
authors.forename: Changyi
authors.initials: C
authors.lastname: Ou
authors.affiliation: The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, PRC, China.
authors.forename: Weibin
authors.initials: W
authors.lastname: Liu
authors.affiliation: University of Virginia, Department of Neurology, Charlottesville, Virginia, 22908, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Conaway
mesh_terms: D006801:Humans; D009157:Myasthenia Gravis / Q000175:diagnosis* / Q000523:psychology*; D011594:Psychometrics; D011788:Quality of Life / Q000523:psychology*; D012189:Retrospective Studies
keywords: MG-QOL15; MG-QOL15r; Rasch analysis; myasthenia; myasthenia gravis; quality of life; revised MG-QOL15