Table 4 Hazard ratio (with 95% CI) for delayed vaccination of MCV1 and MCV2 among children aged 24–35 months, in Zhejiang province (Cox proportional hazard regression, N = 1386) ^a

Number of siblings

1

1

1

2

1.2 (0.9–1.8)

1.1 (0.9–1.5)

≥3

1.6 (1.1–2.0) ^*

2.3 (1.6–3.5) ^**

Place of delivery

Hospital

1

1

Home

1.1 (0.8–1.7)

1.7 (1.3–2.8) ^*

Age of mothers (years)

< 30

1

1

≥30

0.9 (0.7–1.24)

0.8 (0.6–0.9) ^*

Mother’s education level

< senior middle school

1

1

≥ senior middle school

0.8 (0.6–1.2)

0.7 (0.5–0.9) ^*

Maternal employment status

Home fulltime

1

1

Employed

1.2 (0.8–1.5)

2.3 (1.8–4.0) ^**

Immigration status

Resident

1

1

Non-local

2.6 (1.9–4.7) ^*

2.9 (2.2–5.3) ^**

0.9 (0.8–1.0)

0.8 (0.7–0.9) ^*