Title :

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.

Author(s) :

Merz Erin, L [Auteur]
Kwakkenbos, Linda [Auteur]
Carrier, Marie-Eve [Auteur]
Gholizadeh, Shadi [Auteur]
Mills Sarah, D [Auteur]
Fox Rina, S [Auteur]
Jewett Lisa, R [Auteur]
Williamson, Heidi [Auteur]
Harcourt, Diana [Auteur]
Assassi, Shervin [Auteur]
Furst Daniel, E [Auteur]
Gottesman, Karen [Auteur]
Mayes Maureen, D [Auteur]
Moss Tim, P [Auteur]
Thombs Brett, D [Auteur]
Malcarne Vanessa, L [Auteur]

Journal title :

BMJ open

Abbreviated title :

BMJ Open

Volume number :

8

Pages :

e018641

Publication date :

2018-03-06

ISSN :

2044-6055
2044-6055

HAL domain(s) :

Sciences du Vivant [q-bio]

English abstract : [en]

OBJECTIVE: Valid measures of appearance concern are needed in systemic sclerosis (SSc), a rare, disfiguring autoimmune disease. The Derriford Appearance Scale-24 (DAS-24) assesses appearance-related distress related to ...
Show more >OBJECTIVE: Valid measures of appearance concern are needed in systemic sclerosis (SSc), a rare, disfiguring autoimmune disease. The Derriford Appearance Scale-24 (DAS-24) assesses appearance-related distress related to visible differences. There is uncertainty regarding its factor structure, possibly due to its scoring method. DESIGN: Cross-sectional survey. SETTING: Participants with SSc were recruited from 27 centres in Canada, the USA and the UK. Participants who self-identified as having visible differences were recruited from community and clinical settings in the UK. PARTICIPANTS: Two samples were analysed (n=950 participants with SSc; n=1265 participants with visible differences). PRIMARY AND SECONDARY OUTCOME MEASURES: The DAS-24 factor structure was evaluated using two scoring methods. Convergent validity was evaluated with measures of social interaction anxiety, depression, fear of negative evaluation, social discomfort and dissatisfaction with appearance. RESULTS: When items marked by respondents as 'not applicable' were scored as 0, per standard DAS-24 scoring, a one-factor model fit poorly; when treated as missing data, the one-factor model fit well. Convergent validity analyses revealed strong correlations that were similar across scoring methods. CONCLUSIONS: Treating 'not applicable' responses as missing improved the measurement model, but did not substantively influence practical inferences that can be drawn from DAS-24 scores. Indications of item redundancy and poorly performing items suggest that the DAS-24 could be improved and potentially shortened.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Inserm
Université de Lille
CHU Lille

Collections :

• Institut de Recherche Translationnelle sur l'Inflammation (INFINITE) - U1286

Research team(s) :

Immunity, inflammation and fibrsis in auto and allo-reactivity
Glycation from inflammation to aging

Submission date :

2019-03-01T14:08:18Z