Using Optimal Test Assembly Methods for Shortening Patient-Reported Outcome Measures: Development and Validation of the Cochin Hand Function Scale-6 - A Scleroderma Patient-centered Intervention Network (SPIN) Cohort Study. Academic Article uri icon


  • The objective was to develop and validate a short form of the Cochin Hand Function Scale (CHFS), which measures hand disability, for use in systemic sclerosis, using objective criteria and reproducible techniques.Responses on the 18-item CHFS were obtained from English-speaking patients enrolled in the Scleroderma Patient-centered Intervention Network (SPIN) Cohort. CHFS unidimensionality was verified using confirmatory factor analysis, and an item response theory model was fit to CHFS items. Optimal test assembly (OTA) methods identified a maximally precise short form for each possible form length between 1 and 17 items. The final short form selected was the form with the least number of items that maintained statistically equivalent convergent validity, compared to the full-length CHFS, with the Health Assessment Questionnaire - Disability Index (HAQ-DI) and Physical Function domain of PROMIS-29.There were 601 patients included. A 6-item short form of the CHFS (CHFS-6) was selected. The CHFS-6 had a Cronbach's alpha of 0.93. Correlations of the CHFS-6 summed score with HAQ-DI (r = 0.79) and PROMIS-29 Physical Function (r = -0.54) were statistically equivalent to the CHFS (r = 0.81, r = -0.56). The correlation with the full CHFS was high (r = 0.98).The OTA procedure generated a valid short form of the CHFS with minimal loss of information compared to the full-length form. The OTA method used was based on objective, pre-specified criteria, but should be further studied for viability as a general procedure for shortening patient reported outcome measures in health research. This article is protected by copyright. All rights reserved.© 2016, American College of Rheumatology.

publication date

  • March 2016