BMJ Open (Oct 2020)
Assessing differential item functioning for the Social Appearance Anxiety Scale: a Scleroderma Patient-centred Intervention Network (SPIN) Cohort Study
- ,
- Arsène Mekinian,
- Thierry Martin,
- Eric Hachulla,
- Carter Thorne,
- Andrea Benedetti,
- Brett D Thombs,
- Daniel E Furst,
- Virginia Steen,
- Paul R Fortin,
- Vincent Poindron,
- David Launay,
- Luc Mouthon,
- Mandana Nikpour,
- John Varga,
- Benjamin Chaigne,
- Sindhu R Johnson,
- Sébastien Rivière,
- Isabelle Boutron,
- Daphna Harel,
- Linda Kwakkenbos,
- Marie-Eve Carrier,
- Karen Nielsen,
- Alexandra Portales,
- Susan J Bartlett,
- Vanessa L Malcarne,
- Murray Baron,
- Karen Gottesman,
- Maureen D Mayes,
- Warren R Nielson,
- Robert Riggs,
- Maureen Sauve,
- Fredrick Wigley,
- Shervin Assassi,
- Angela Costa Maia,
- Ghassan El-Baalbaki,
- Carolyn Ells,
- Kim Fligelstone,
- Catherine Fortune,
- Tracy Frech,
- Dominique Godard,
- Marie Hudson,
- Ann Impens,
- Yeona Jang,
- Ann Tyrell Kennedy,
- Annett Körner,
- Maggie Larche,
- Catarina Leite,
- Carlo Marra,
- Janet Pope,
- Russell J Steele,
- Maria E Suarez-Almazor,
- Joep Welling,
- Durhane Wong-Rieger,
- Christian Agard,
- Alexandra Albert,
- Marc André,
- Guylaine Arsenault,
- Ilham Benzidia,
- Sabine Berthier,
- Lyne Bissonnette,
- Gilles Boire,
- Alessandra Bruns,
- Patricia Carreira,
- Marion Casadevall,
- Lorinda Chung,
- Pascal Cohen,
- Pierre Dagenais,
- Christopher Denton,
- Robyn Domsic,
- Sandrine Dubois,
- James V Dunne,
- Bertrand Dunogue,
- Alexia Esquinca,
- Regina Fare,
- Dominique Farge-bancel,
- Anna Gill,
- Jessica Gordon,
- Brigitte Granel-Rey,
- Claire Grange,
- Genevieve Gyger,
- Pierre-Yves Hatron,
- Ariane L Herrick,
- Adrian Hij,
- Monique Hinchcliff,
- Alena Ikic,
- Niall Jones,
- Suzanne Kafaja,
- Nader Khalidi,
- Marc Lambert,
- Patrick Liang,
- Hélène Maillard,
- Joanne Manning,
- Maria Martin,
- Ariel Masetto,
- François Maurier,
- Sheila Melchor,
- Susanna Proudman,
- Alexis Régent,
- David Robinson,
- Esther Rodriguez,
- Sophie Roux,
- Perrine Smets,
- Doug Smith,
- Vincent Sobanski,
- Robert Spiera,
- Wendy Stevens,
- Evelyn Sutton,
- Benjamin Terrier,
- Pearce Wilcox,
- Shadi Gholizadeh,
- François Rannou,
- Lindsay Cronin,
- Stephen Elrod,
- Cornelia van den Ende,
- Amy Gietzen,
- Christelle Nguyen,
- Michelle Richard,
- Ken Rozee,
- Anne A. Schouffoer,
- Nancy Stephens,
- Chase Correia,
- Artur Jose de B. Fernandes,
- Nancy Maltez,
- Isabelle Marie,
- Lydia Tao,
- Sami Harb,
- Elana J Bernstein,
- Sophia J Sommer,
- Shirley Haslam Geneviève Guillot,
- Tatiana Sofia Rodriguez Reyna,
- Sabrina Hoa,
- Angelica Bourgeault,
- Andrea Carboni Jiménez
Affiliations
- 3University College London
- Arsène Mekinian
- Département de Médecine Interne et Immunologie Clinique DHUi2B, Hôpital Saint-Antoine, Paris, France
- Thierry Martin
- 2 Centre National de Références des Maladies Systémiques et Autoimmunes Rares Est Sud-Ouest (RESO), Université de Strasbourg, Strasbourg, France
- Eric Hachulla
- Service de Médecine Interne et Immunologie Clinique, Centre de référence des maladies autoimmunes systémiques rares du Nord et Nord-Ouest de France (CeRAINO), Univ. Lille, Inserm, CHU Lille, U1286 - INFINITE - Institute for Translational Research in Inflammation, F-59000, Lille, France
- Carter Thorne
- 9Newmarket Medical Center, Newmarket, Canada
- Andrea Benedetti
- Department of Medicine, McGill University, Montreal, Québec, Canada
- Brett D Thombs
- professor
- Daniel E Furst
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
- Virginia Steen
- Paul R Fortin
- Division of Rheumatology, CHU de Québec, Universite Laval, Quebec City, Quebec, Canada
- Vincent Poindron
- 3Centre National de Référence des maladies auto-immunes et systémiques rares Est/Sud-Ouest (RESO)
- David Launay
- Luc Mouthon
- Department of Internal Medicine, National Referral Center for Rare Systemic Autoimmune Diseases, Université Paris Cité, Hôpital Cochin, Paris, France
- Mandana Nikpour
- Department of Medicine, The University of Melbourne Medicine at St Vincent`s Hospital, Fitzroy, Victoria, Australia
- John Varga
- Division of Rheumatology, University of Michigan, Ann Arbor, Michigan, USA
- Benjamin Chaigne
- 6AP-HP Cochin Hospital, Paris, France
- Sindhu R Johnson
- 4 Division of Rheumatology, Department of Medicine, Toronto Western Hospital, University Health Network, Mount Sinai Hospital, and Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada
- Sébastien Rivière
- Service de médecine interne, AP-HP, Hôpital Saint Antoine, Sorbonne Universite, Paris, France
- Isabelle Boutron
- professor of epidemiology
- Daphna Harel
- Applied Statistics, Social Science, Humanities, New York University, New York, New York, USA
- Linda Kwakkenbos
- lecturer
- Marie-Eve Carrier
- Lady Davis Institute for Medical Research, Montreal, Québec, Canada
- Karen Nielsen
- Alexandra Portales
- Susan J Bartlett
- Department of Medicine, McGill University, Montreal, Québec, Canada
- Vanessa L Malcarne
- 9 Department of Psychology, San Diego State University, San Diego, California, USA
- Murray Baron
- McGill University, Division of Rheumatology, Jewish General Hospital, Montreal, Quebec, Canada
- Karen Gottesman
- National Scleroderma Foundation, Los Angeles, California, USA
- Maureen D Mayes
- Division of Rheumatology and Clinical Immunogenetics, The University of Texas Health Science Center John P and Katherine G McGovern Medical School, Houston, Texas, USA
- Warren R Nielson
- Robert Riggs
- Maureen Sauve
- vice president for advocacy and public relations
- Fredrick Wigley
- Shervin Assassi
- Division of Rheumatology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
- Angela Costa Maia
- Ghassan El-Baalbaki
- 11 Department of Psychology, Université du Québec à Montréal, Montreal, Quebec, Canada
- Carolyn Ells
- School of Population and Global Health, McGill University, Montreal, Quebec, Canada
- Kim Fligelstone
- 11 Federation of European Scleroderma Associations (FESCA), Brussels, Belgium
- Catherine Fortune
- Tracy Frech
- University of Utah, Salt Lake City, United States of America
- Dominique Godard
- Marie Hudson
- McGill University, Montreal, Canada
- Ann Impens
- Yeona Jang
- Ann Tyrell Kennedy
- Annett Körner
- Maggie Larche
- Catarina Leite
- Portuguese Association of Patients with Scleroderma, Monção, Portugal
- Carlo Marra
- School of Pharmacy, University of Otago Division of Health Sciences, Dunedin, New Zealand
- Janet Pope
- Department of Medicine, Western University, London, Ontario, Canada
- Russell J Steele
- Department of Mathematics and Statistics, McGill University, Montreal, Canada
- Maria E Suarez-Almazor
- The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Joep Welling
- FESCA Patient Research Partner, Utrecht, The Netherlands
- Durhane Wong-Rieger
- Christian Agard
- Internal Medicine, Nantes University Hospital, Nantes, France
- Alexandra Albert
- Clinique Multidisciplinaire de Neuville, Neuville, Quebec, Canada
- Marc André
- Inserm U1071, M2iSH, USC-INRA 1382, Université Clermont Auvergne, Clermont-Ferrand, Auvergne-Rhône-Alpes, France
- Guylaine Arsenault
- Ilham Benzidia
- Sabine Berthier
- Internal Medicine, Bocage Hospital, Dijon, France
- Lyne Bissonnette
- Gilles Boire
- 6Université de Sherbrooke, Sherbrooke, Canada
- Alessandra Bruns
- Patricia Carreira
- H 12 Octubre, Madrid, Spain
- Marion Casadevall
- Lorinda Chung
- Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, California, USA
- Pascal Cohen
- 1 Department of Internal Medicine, National Reference Center for Rare Systemic Autoimmune Diseases, AP-HP.Centre, Hospital Cochin, Paris, France
- Pierre Dagenais
- Christopher Denton
- Robyn Domsic
- Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Sandrine Dubois
- James V Dunne
- Bertrand Dunogue
- Hôpital Cochin, Department of Internal Medicine, National Referral Center for Rare Systemic Autoimmune Diseases, Université Paris Cité, Hôpital Cochin, Paris, France
- Alexia Esquinca
- Regina Fare
- Dominique Farge-bancel
- Anna Gill
- Jessica Gordon
- Department of Rheumatology, Department of Medicine, Hospital for Special Surgery, New York, New York, USA
- Brigitte Granel-Rey
- Claire Grange
- Genevieve Gyger
- Pierre-Yves Hatron
- 2Dept. of Internal Medicine and Clinical Immunology, National Referral Centre for rare Systemic Auto-immune Diseases North and North-West of France (CeRAINO), CHU Lille, Hôpital Claude Huriez, Lille
- Ariane L Herrick
- Centre for Musculoskeletal Research, The University of Manchester, Salford Royal NHS Foundation Trust,Manchester Academic Health Science Centre, Manchester, UK
- Adrian Hij
- Monique Hinchcliff
- associate professor
- Alena Ikic
- Niall Jones
- Suzanne Kafaja
- Internal Medicine/Division of Rheumatology, University of California Los Angeles, Los Angeles, California, USA
- Nader Khalidi
- Marc Lambert
- Patrick Liang
- Centre intégré universitaire de santé et de services sociaux de l`Estrie - Centre Hospitalier Universitaire de Sherbrooke (CIUSSSE-CHUS), Quebec, Canada
- Hélène Maillard
- Joanne Manning
- Maria Martin
- 3Hospital Doce de octubre, Madrid, Spain
- Ariel Masetto
- University of Sherbrooke, Sherbrooke, Canada
- François Maurier
- Private Metz Hospital, Metz, France
- Sheila Melchor
- University Hospital 12 de Octubre, Madrid, Spain
- Susanna Proudman
- 1University of Adelaide, Discipline of Medicine, Adelaide, Australia
- Alexis Régent
- 3Cochin Hospital, Paris, France
- David Robinson
- Esther Rodriguez
- Sophie Roux
- Centre intégré universitaire de santé et de services sociaux de l`Estrie - Centre Hospitalier Universitaire de Sherbrooke (CIUSSSE-CHUS), Quebec, Canada
- Perrine Smets
- 7CHU de Clermont-Ferrand, Clermont-Ferrand, France
- Doug Smith
- University of Ottawa, Division of Rheumatology, Department of Medicine, Ottawa, Ontario, Canada
- Vincent Sobanski
- Robert Spiera
- Hospital for Special Surgery, New-York, United States of America
- Wendy Stevens
- Department of Molecular Medicine and Haematology, University of the Witwatersrand, Johannesburg-Braamfontein, South Africa
- Evelyn Sutton
- Benjamin Terrier
- Department of Internal Medicine, National Referral Center for Rare Systemic Autoimmune Diseases, Université Paris Cité, Hôpital Cochin, Paris, France
- Pearce Wilcox
- Shadi Gholizadeh
- San Diego Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California, San Diego, California, USA
- François Rannou
- Hôpital Cochin, Paris, Île-de-France, France
- Lindsay Cronin
- Stephen Elrod
- Cornelia van den Ende
- 1Sint Maartenskliniek, Department of Rheumatology, Nijmegen, Netherlands
- Amy Gietzen
- National Scleroderma Foundation Tri-State Chapter, Buffalo, New York, USA
- Christelle Nguyen
- Service de Rééducation et de Réadaptation de l’Appareil Locomoteur et des Pathologies du Rachis, hôpital Cochin, Paris, France
- Michelle Richard
- Scleroderma Atlantic, Halifax, Nova Scotia, Canada
- Ken Rozee
- Anne A. Schouffoer
- Nancy Stephens
- Chase Correia
- Artur Jose de B. Fernandes
- Nancy Maltez
- University of Ottawa, Ottawa, Canada
- Isabelle Marie
- Bicêtre Hospital, Department of Paediatric Rheumatology, Reference centre for Auto-inflammatory diseases, RESRIP French network, Le Kremlin Bicêtre, France
- Lydia Tao
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Québec, Canada
- Sami Harb
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Québec, Canada
- Elana J Bernstein
- Division of Rheumatology, Columbia University Vagelos College of Physicians and Surgeons, New York, New York, USA
- Sophia J Sommer
- Applied Statistics, Social Science and Humanities, New York University, New York, New York, USA
- Shirley Haslam Geneviève Guillot
- Tatiana Sofia Rodriguez Reyna
- Sabrina Hoa
- University of Montreal, Montreal, Canada
- Angelica Bourgeault
- Andrea Carboni Jiménez
- DOI
- https://doi.org/10.1136/bmjopen-2020-037639
- Journal volume & issue
-
Vol. 10,
no. 10
Abstract
Objectives The Social Appearance Anxiety Scale (SAAS) is a 16-item questionnaire developed to evaluate fear of appearance-based evaluation by others. The primary objective of this research was to investigate the existence of differential item functioning (DIF) for the 16 SAAS items, comparing patients who completed the SAAS in English and French, either to confirm that scores are comparable or provide guidance on calculating comparable scores. A secondary research objective was to investigate the existence of DIF based on sex and disease status. A tertiary research objective was to assess DIF related to language, sex, and disease status on the recently developed SAAS-5.Design This was a cross-sectional analysis using baseline data from patients enrolled in the Scleroderma Patient-centred Intervention Network (SPIN).Setting SPIN patients included in the present study were enrolled at 43 centres in Canada, USA, UK, France and Australia, with questionnaires completed in April 2014 to July 2019.Participants 1640 SPIN patients completed the SAAS in French (n=600) or English (n=1040).Primary and secondary measures The SAAS was collected along with demographic and disease characteristics.Results Six items were identified with statistically significant language-based DIF, four with sex-based DIF and one with disease type-based DIF. However, factor scores before and after accounting for DIF were similar (Pearson correlation >0.99), and individual score differences were small. This was true for both the full and shortened versions of the SAAS.Conclusion SAAS and SAAS-5 scores are comparable across language, sex, and disease-type, despite small differences in how patients respond to some items.
