Development of an extension of the OMERACT Summary of Measurement Properties table to capture equity considerations: SOMP-Equity.

Objective: To develop an equity extension of the OMERACT Summary of Measurement Properties (SOMP) Table, SOMP Equity to describe whether a patient reported outcome measure (PROM) works well among patients of diverse languages and cultures, education levels, and other population characteristics.

Methods: We used the PROGRESS-Plus framework to categorize equity characteristics assessed in trials of PROM. PROGRESS refers to Place of residence, Race/ethnicity/culture/language, Occupation, Gender/sex, Religion, Education, Socioeconomic status, and Social Capital, while the 'plus' captures additional characteristics, such as age. We pilot tested our SOMP Equity Extension using the Health Assessment Questionnaire (HAQ) as a prototypical PROM.

Results: The SOMP Equity Extension retains the same columns as the original OMERACT SOMP (domain match, feasibility, construct validity, test-retest reliability, longitudinal construct validity, clinical trial discrimination, thresholds of meaning) but uses the PROGRESS-Plus characteristics as rows. We found several examples of studies of the HAQ which had assessed one or more PROGRESS-Plus characteristics.

Conclusions: The most commonly reported equity considerations were related to language. OMERACT Equity virtual meeting participants were polled and they indicated that the SOMP Equity Extension is useful for highlighting and tracking equity considerations for OMERACT Core Outcome Measurement Instruments.