. 2014 Jun 25;9(6):e100651. doi: 10.1371/journal.pone.0100651

Table 1. Baseline Characteristics Study Population.

	10-year-olds	12-year-olds	15-year-olds
No. of enrolled participants	91	91	86
Mean age at enrolment (T0); years (±SD)	9.9 (0.3)	12.0 (0.3)	15.0 (0.3)
Female; No. (%)	53 (58)	44 (48)	41 (48)
Mean age at MenCC vaccine priming^a; years (±SD)	1.2 (0.1)	2.7 (0.3)	5.8 (0.4)
Mean interval since primary MenCC vaccination and T0^b; years (±SD)	8.7 (0.3)	9.3 (0.1)	9.2 (0.2)

a. All participants were primed with one vaccination with the Meningococcal serogroup C polysaccharide conjugated to tetanus toxoid vaccine (MenC-TT, Baxter) and received a booster with the same vaccine at the beginning of the study (T0). Individual immunization histories were verified by checking personal vaccination cards or from centralized immunization records.

b. Intervals slightly differed between groups (separate t-tests; P<0.001). Further testing showed no relation between interval duration and antibody levels (data not shown). Analyses were therefore not adjusted for this interval.