Top 10 things to know about lupus activity measures.

Accurately measuring lupus disease activity has been a demanding and still unresolved task, considering the complex multisystem nature of the disease and its variability over time and between patients. Various available tools for measurement of lupus disease activity may detect clinical improvement and/or deterioration and can be global or organ-focused. Several measures have demonstrated validity, reliability, and sensitivity to change in observational studies, and some were found useful in randomized controlled trials. Evaluation of their content and metric properties and critical review of their strengths and weaknesses facilitates selection of the appropriate tool according to the outcome of interest, and forms the basis for their optimization. In this review, we highlight recent progress in lupus disease activity measures and point to future directions in this field, with a focus on novel composite measurements derived by combining outcome measures in ways that might compensate for their individual deficiencies.