Researchers recruited patients from 14 university hospitals in France between March 2008 and January 2011. Patients received infusions of rituximab (1 g) or placebo at the beginning of the trial and at week 2. (A course of rituximab is generally given once every 6 months, consisting of 2 infusions given 2 weeks apart.) Researchers measured changes in overall disease activity, pain, fatigue, and dryness at weeks 6, 16, and 24 using visual analogue scales (VASs). A VAS consists of a 100-mm line on which patients mark symptom intensity from low to high. The primary outcome was an improvement of at least 30 mm in at least 2 of the 4 VAS scores at week 24 compared with the start of the trial.