Risk ratios of SC to the pandemic influenza vaccine when treated with either 1 or 2 doses when comparing anti-CD20–treated patients to disease controls. (A) On active therapy (<3 months from therapy). (B) Three to 6 months from therapy. (C) Six to 12 months from therapy. (D) More than 12 months from therapy. Events, the number of patients with SC response to vaccination; Total, the total number of patients assessed for SC response to vaccination; Weight, the weighted contribution of each study to the meta-analysis.