Hydroxychloroquine in systemic lupus erythematosus

To the Editor: The Canadian Hydroxychloroquine Study Group deserves credit for its attempt to test the effectiveness of hydroxychloroquine in systemic lupus erythematosus (Jan. 17 issue).¹ Unfortunately, there are two important aspects that need to be considered in this study, since they oppose the conclusions reached by the authors. First, most manifestations of lupus, especially arthritis and rashes, are symptomatic; if a drug controls these manifestations, there should be subjective awareness of its use. But the patients in this study were right only half the time (53 percent) in guessing whether they were taking the drug or placebo — no.