Research methods

Factor structure and convergent validity of the Derriford Appearance Scale-24 using standard scoring versus treating ‘not applicable’ responses as missing data: a Scleroderma Patient-centered Intervention Network (SPIN) cohort study

Erin L Merz, Linda Kwakkenbos, Marie-Eve Carrier, Shadi Gholizadeh, Sarah D Mills, Rina S Fox, Lisa R Jewett, Heidi Williamson, Diana Harcourt, Shervin Assassi, Daniel E Furst, Karen Gottesman, Maureen D Mayes, Tim P Moss, Brett D Thombs, Vanessa L Malcarne, on behalf of the SPIN Investigators, Murray Baron, Susan J Bartlett, Frank Van Den Hoogen, Luc Mouthon, Warren R Nielson, Robert Riggs, Maureen Sauve, Fredrick Wigley, Angela Costa Maia, Ghassan El-Baalbaki, Carolyn Ells, Cornelia Van Den Ende, Kim Fligelstone, Catherine Fortune, Tracy Frech, Dominique Godard, Daphna Harel, Marie Hudson, Ann Impens, Yeona Jang, Sindhu R Johnson, Ann Tyrell Kennedy, Annett Körner, Maggie Larche, Catarina Leite, Carlo Marra, Karen Nielsen, Janet Pope, Alexandra Portales, Tatiana Sofia Rodriguez Reyna, Anne A Schouffoer, Russell J Steele, Maria E Suarez-Almazor, Joep Welling, Durhane Wong-Rieger, Christian Agard, Alexandra Albert, Marc André, Guylaine Arsenault, Nouria Benmostefa, Ilham Benzida, Sabine Berthier, Lyne Bissonnette, Gilles Boire, Alessandra Bruns, Patricia Carreira, Marion Casadevall, Benjamin Chaigne, Lorinda Chung, Pascal Cohen, Pierre Dagenais, Christopher Denton, Robyn Domsic, James V Dunne, Dominique Farge-Bancel, Paul Fortin, Anna Gill, Jessica Gordon, Brigitte Granel-Rey, Claire Grange, Genevieve Gyger, Eric Hachulla, Pierre-Yves Hatron, Ariane L Herrick, Adrian Hij, Monique Hinchcliff, Alena Ikic, Niall Jones, Artur Jose De B Fernandes, Suzanne Kafaja, Nader Khalidi, Benjamin Korman, Marc Lambert, David Launay, Patrick Liang, Jonathan London, Joanne Manning, Thierry Martin, Ariel Masetto, Arsene Mekinian, Romain Paule, Alexis Regent, Sébastien Rivière, David Robinson, Sophie Roux, Perrine Smets, Doug Smith, Vincent Sobanski, Robert Spiera, Virginia Steen, Evelyn Sutton, Benjamin Terrier, Carter Thorne, John Varga, Pearce Wilcox, Vanessa C Delisle, Brooke Levis, Mia R Pepin

10.1136/bmjopen-2017-018641

March 6, 2018