Development and validation of the Dermatology Social Comparison (DSC) Scale

Ellie Choi; Ruochen Du; Yik W Yew; Valencia Long; Hazel H Oon; Nisha S Chandran; Phillip Phan; Yiong H Chan; Jose M Valderas

doi:10.1111/ijd.17146

Development and validation of the Dermatology Social Comparison (DSC) Scale

Int J Dermatol. 2024 Apr 9. doi: 10.1111/ijd.17146. Online ahead of print.

Authors

Ellie Choi^{1

2}, Ruochen Du³, Yik W Yew^{4

5}, Valencia Long¹, Hazel H Oon⁴, Nisha S Chandran^{1

2}, Phillip Phan^{2

6}, Yiong H Chan³, Jose M Valderas^{7

8}

Affiliations

¹ Division of Dermatology, Department of Medicine, National University Healthcare System, Singapore, Singapore.
² Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
³ Biostatistics Unit, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
⁴ Dermatology, National Skin Centre, Singapore, Singapore.
⁵ Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
⁶ Carey Business School, Johns Hopkins University, Baltimore, USA.
⁷ Centre for Research in Health System Performance, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
⁸ Department of Family Medicine, National University Healthcare System, Singapore, Singapore.

PMID: 38594911
DOI: 10.1111/ijd.17146

Abstract

Background: Social comparison, the process of evaluating one's characteristics in relation to others, influences individuals' self-perception and behavior. However, instruments are scarce for assessing social comparison in the medical setting.

Objectives: Our aim was to develop and validate a new scale for assessing social comparison.

Materials and methods: Seven statements were developed, encompassing the perceived normality of having rashes, the tendency to compare their situation with others, and the emotional response when seeing someone better or worse off than themselves. The instrument was piloted in 15 patients for readability and face validity, then prospectively validated using modern psychometric methods in 1,053 adult patients with eczema or psoriasis from three tertiary dermatological centers in Singapore.

Results: Of 1,053 adult patients, 802 (76.2%) had eczema, and 251 (23.8%) had psoriasis. Exploratory factor analysis (using a 70% sample split) showed a single factor model comprising three questions (Eigenvalue: 1.4). Confirmatory factor analysis with the remaining 30% of the sample confirmed an excellent model fit. Cronbach's alpha was 0.7, and inter-item correlations ranged from 0.42 to 0.46. In the Rasch analysis, item fit statistics and item characteristic curves showed appropriate discrimination between response options, although reliability was suboptimal with a person separation reliability of 0.63.

Conclusions: Comprising 3 questions, the newly derived social comparison scale showed acceptable psychometrics as a measure of social comparison for clinical and research purposes in dermatology. Its brief nature likely results from its brevity and applicability to conditions beyond eczema and psoriasis, which warrants further investigation.

Keywords: disease severity; eczema; health outcomes; patient‐centered care; patient‐reported measures; patient–physician relationship; psoriasis; quality of life; questionnaire validation; social comparison; symptom burden.

Abstract

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