The Comparability of English, French and Dutch Scores on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F): An Assessment of Differential Item Functioning in Patients with Systemic Sclerosis

• Linda Kwakkenbos ,

  * E-mail: kwakkenbosL@gmail.com

  Affiliations Department of Psychiatry, McGill University, Montréal, Québec, Canada, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada

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• Linda M. Willems,

  Affiliation Department of Rheumatology, Sint Maartenskliniek Nijmegen, The Netherlands

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• Murray Baron,

  Affiliations Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada, Department of Medicine, McGill University, Montréal, Québec, Canada

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• Marie Hudson,

  Affiliations Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada, Department of Medicine, McGill University, Montréal, Québec, Canada

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• David Cella,

  Affiliation Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America

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• Cornelia H. M. van den Ende,

  Affiliation Department of Rheumatology, Sint Maartenskliniek Nijmegen, The Netherlands

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• Brett D. Thombs,

  Affiliations Department of Psychiatry, McGill University, Montréal, Québec, Canada, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada, Department of Medicine, McGill University, Montréal, Québec, Canada, Departments of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montréal, Québec, Canada, Educational and Counselling Psychology, McGill University, Montréal, Québec, Canada, Psychology, McGill University, Montréal, Québec, Canada, School of Nursing, McGill University, Montréal, Québec, Canada

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• and the Canadian Scleroderma Research Group

  ¶Membership of the Canadian Scleroderma Research Group is provided in the Acknowledgments.

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