TY - JOUR
T1 - Shortening patient-reported outcome measures through optimal test assembly
T2 - Application to the Social Appearance Anxiety Scale in the Scleroderma Patient-centered Intervention Network Cohort
AU - Harel, Daphna
AU - Mills, Sarah D.
AU - Kwakkenbos, Linda
AU - Carrier, Marie Eve
AU - Nielsen, Karen
AU - Portales, Alexandra
AU - Bartlett, Susan J.
AU - Malcarne, Vanessa L.
AU - Thombs, Brett D.
N1 - Funding Information:
Funding SPIN has been funded by research grants from the Canadian Institutes of Health Research (TR3-119192, PJT-148504 and PJT-149073), the Arthritis Society, the Scleroderma Society of Ontario and Scleroderma Canada. SPIN has also received support from the Lady Davis Institute for Medical Research of the Jewish General Hospital, Montreal, Canada, from McGill University, Montreal, Canada, and from Sclérodermie Québec. SDM receives funding from the Cancer Control Education Program at the University of North Carolina, Chapel Hill (National Cancer Institute award T32 CA057726). LK was supported by a CIHR Banting Postdoctoral Fellowship. BDT was supported by a Fonds de recherche Santé -Québec (FRQS) researcher salary award. Authors had full access to the data and take responsibility for the integrity of the data and the accuracy of the data analysis.
Publisher Copyright:
© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
PY - 2019/2/1
Y1 - 2019/2/1
N2 - Objectives The Social Appearance Anxiety Scale (SAAS) is a 16-item measure that assesses social anxiety in situations where appearance is evaluated. The objective was to use optimal test assembly (OTA) methods to develop and validate a short-form SAAS based on objective and reproducible criteria. Design This study was a cross-sectional analysis of baseline data from adults enrolled in the Scleroderma Patient-centered Intervention Network (SPIN) Cohort. Setting Adults in the SPIN Cohort in the present study were enrolled at 28 centres in Canada, the USA and the UK. Participants The SAAS was administered to 926 adults with scleroderma. Primary and secondary measures The SAAS, Brief Fear of Negative Evaluation II (BFNE II), Brief Satisfaction with Appearance Scale (Brief-SWAP), Patient Health Questionnaire-8 (PHQ8) and Social Interaction Anxiety Scale-6 (SIAS-6) were collected, as well as demographic characteristics. Results OTA methods identified a maximally informative shortened version for each possible form length between 1 and 15 items. The final shortened version was selected based on prespecified criteria for reliability, concurrent validity and statistically equivalent convergent validity with the BFNE II scale. A five-item short version was selected (SAAS-5). The SAAS-5 had a Cronbach's α of 0.95 and had high concurrent validity with the full-length form (r=0.97). The correlation of the SAAS-5 with the BFNE II was 0.66, which was statistically equivalent to that of the full-length form. Furthermore, the correlation of the SAAS-5 with the two subscales of the Brief-SWAP, and the SIAS-6, were statistically equivalent to that of the full-length form. Conclusions OTA was an efficient method for shortening the full-length SAAS to create the SAAS-5.
AB - Objectives The Social Appearance Anxiety Scale (SAAS) is a 16-item measure that assesses social anxiety in situations where appearance is evaluated. The objective was to use optimal test assembly (OTA) methods to develop and validate a short-form SAAS based on objective and reproducible criteria. Design This study was a cross-sectional analysis of baseline data from adults enrolled in the Scleroderma Patient-centered Intervention Network (SPIN) Cohort. Setting Adults in the SPIN Cohort in the present study were enrolled at 28 centres in Canada, the USA and the UK. Participants The SAAS was administered to 926 adults with scleroderma. Primary and secondary measures The SAAS, Brief Fear of Negative Evaluation II (BFNE II), Brief Satisfaction with Appearance Scale (Brief-SWAP), Patient Health Questionnaire-8 (PHQ8) and Social Interaction Anxiety Scale-6 (SIAS-6) were collected, as well as demographic characteristics. Results OTA methods identified a maximally informative shortened version for each possible form length between 1 and 15 items. The final shortened version was selected based on prespecified criteria for reliability, concurrent validity and statistically equivalent convergent validity with the BFNE II scale. A five-item short version was selected (SAAS-5). The SAAS-5 had a Cronbach's α of 0.95 and had high concurrent validity with the full-length form (r=0.97). The correlation of the SAAS-5 with the BFNE II was 0.66, which was statistically equivalent to that of the full-length form. Furthermore, the correlation of the SAAS-5 with the two subscales of the Brief-SWAP, and the SIAS-6, were statistically equivalent to that of the full-length form. Conclusions OTA was an efficient method for shortening the full-length SAAS to create the SAAS-5.
KW - generalized partial credit model
KW - optimal test assembly
KW - patient reported outcome measure
KW - short form
KW - systemic sclerosis
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U2 - 10.1136/bmjopen-2018-024010
DO - 10.1136/bmjopen-2018-024010
M3 - Article
C2 - 30798308
AN - SCOPUS:85062063238
SN - 2044-6055
VL - 9
JO - BMJ Open
JF - BMJ Open
IS - 2
M1 - e024010
ER -