Table 3 Odds ratios and 95 % confidence intervals for risk factors of nasopharyngeal carriage of pneumococcus or Haemophilus influenzae type b (Hib) among 614 children in Shanghai, 2009

Spring vs autumn

0.46 (0.27, 0.78)

0.0044

0.78 (0.37, 1.64)

0.5166

Age of child

0.4703

0.9533

 12 months

1.46 (0.69, 3.09)

0.95 (0.34, 2.65)

 13–14 months

1.34 (0.64, 2.84)

1.08 (0.39, 2.94)

 15–16 months

0.94 (0.42, 2.09)

1.21 (0.43, 3.40)

 17–18 months

ref

ref

Local vs non-local residency

0.30 (0.13, 0.69)

0.0048

0.45 (0.09, 2.32)

0.3388

Urbanicity

0.1773

0.1067

 Urban

0.66 (0.34, 1.25)

0.43 (0.19, 0.97)

 Suburban

1.06 (0.46, 2.44)

0.63 (0.21, 1.85)

 Rural

ref

ref

Father’s education

0.4037

0.4163

 Primary school or less

0.79 (0.21, 2.90)

8.53 (0.70, 103.52)

 Junior high

1.10 (0.52, 2.34)

5.61 (0.60, 52.28)

 High school/vocational

0.66 (0.29, 1.52)

5.29 (0.58, 48.43)

 College or more

ref

ref

Household income

0.5869

 <2000 yuan

2.21 (0.48, 10.18)

 2000–4999 yuan

2.19 (0.47, 10.18)

 ≥5000 yuan

ref

Size of house

0.1010

 <18 m²

2.06 (0.67, 6.32)

 18–29 m²

2.96 (0.99, 8.85)

 30–69 m²

1.17 (0.35, 3.88)

 ≥70 m²

ref

≥1 dose Hib vaccine vs no doses

0.55 (0.24, 1.27)

0.1607