The assessment of disease activity in systemic lupus erythematosus (SLE) is a 
task faced by clinicians in every day care, but it is also required for clinical 
research and in randomised controlled trials. It is crucial to distinguish 
disease activity from infection, chronic damage and co-morbid disease. Over the 
past 20 years, many indices have been developed to objectively measure lupus 
disease activity and several of these have been validated. The most widely used 
indices are the British Isles Lupus Assessment Group (BILAG) index, the European 
Consensus Lupus Activity Measurement (ECLAM), the Systemic Lupus Activity 
Measure (SLAM), the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) 
and the Lupus Activity Index (LAI). All these indices have been validated and 
have excellent reliability, validity and responsiveness to change. In addition 
to the assessment of disease activity, the evaluation of damage using the 
validated SLICC/ACR damage index and health-related quality of life is advised 
for clinical research.