Fig. 3From: A high throughput serum bactericidal assay for antibodies to Haemophilus influenzae type bLevey-Jennings charts of serum bactericidal indices of three QC sera (a QCVH, b QCH, and c QCL) over 6 years. Runs 1–7 were performed in 2006, runs 8–15 in 2009, runs 16 and 17 in 2011, and runs 18–20 in 2012. The two dotted and dashed lines in each panel indicate one and two standard deviations (SDs) away from the mean, respectivelyBack to article page