. 2013 Jan 4;9(2):277–282. doi: 10.4161/hv.22714

Table 2. Statistic analysis of the frequency of adverse events (AE) following yellow fever immunization in persons aged ≥ 60 y, in São Paulo, Brazil, 2009–2010.

Systemic AE		n/total (%)	Statistic test	p
Age (years)	60–69	69/437 (15.8)	χ2 = 3.638	0.056
Age (years)	> 70	28/263 (10.6)	χ2 = 3.638	0.056
Sex	Female	52/393 (13.2)	χ2 = 0.294	0.588
Sex	Male	45/307 (14.7)	χ2 = 0.294	0.588
Altered immunocompetence	Yes	2/8 (25)	Fisher = 0.841	0.359
Altered immunocompetence	No	95/692 (13.7)	Fisher = 0.841	0.359
1^rst YF vaccine dose*	Yes	67/382 (17.5)	χ2 = 8.397	0.004
1^rst YF vaccine dose*	No	26/273 (9.5)	χ2 = 8.397	0.004
Local AE
Age (years)	60–69	10/437 (2.1)	χ2 = 0.97	0.756
Age (years)	> 70	7/263 (2.7)	χ2 = 0.97	0.756
Sex	Female	15/393 (3.8)	χ2 = 7.288	0.007
Sex	Male	2/307 (0.7)	χ2 = 7.288	0.007
Altered immunocompetence	Yes	1/8 (12.5)	Fisher = 3.459	0.063
Altered immunocompetence	No	16/692 (2.3)	Fisher = 3.459	0.063
1^rst YF vaccine dose*	Yes	9/382 (2.4)	χ2 = 0.029	0.865
1^rst YF vaccine dose*	No	7/273 (2.6)	χ2 = 0.029	0.865
Total AE
Age (years)	60–69	74/437 (16.9)	χ2 = 2.439	0.118
Age (years)	> 70	33/263 (12.5)	χ2 = 2.439	0.118
Sex	Female	62/393 (15.8)	χ2 = 0.166	0.683
Sex	Male	45/307 (14.7)	χ2 = 0.166	0.683
Altered immunocompetence	Yes	2/8 (25)	Fisher = 0.589	0.443
Altered immunocompetence	No	105/692 (15.2)	Fisher = 0.589	0.443
1^rst YF vaccine dose*	Yes	73/382 (19.1)	χ2 = 7.923	0.005
1^rst YF vaccine dose*	No	30/273 (11)	χ2 = 7.923	0.005

Note: *Information on previous YF vaccination was available for only 655 of 700 subjects who were sucessfully contacted for assessment of AE following vaccination.