TABLE 2

Characteristics of children with varicella and matched controls

Clinical characteristicsValueP valuea
Children with varicella (n = 106)Controls (n = 106)
Age (yr)
    Mean ± SD5.2 ± 2.95.2 ± 3.0
    Median44
    Range1–131–14
No. (%) of females50 (47.2)50 (47.2)
No. (%) who received varicella vaccine100 (94.3)103 (97.2)0.3173
No. (%) with varicella vaccination before 12 months of age0 (0.0)1 (1.2)0.4885
No. (%) with varicella vaccination before 15 months of age75 (84.3)76 (90.5)0.2585
Mean ± SD age at varicella vaccination (mo)b14.9 ± 9.213.3 ± 4.20.1403
No. (%) who received varicella vaccine within 28 days of MMR vaccinec15 (21.7)41 (58.5)<.0001
  • a P values were obtained by McNemar's test except age at varicella vaccination, which was obtained by a paired t test.

  • b The date of varicella vaccination was obtained in 89 children in the varicella group and 84 children in the control group.

  • c Duration from MMR vaccination to varicella vaccination was obtained in 69 children in the varicella group and 70 children in the control group.