Table 1 Distribution of characteristics of the study population, children born during 2012–2018 in Ningbo, China
Demographics | No. | Frequency(%) |
|---|---|---|
Total | 716,178 | 100.00 |
Sex | ||
Male | 379,102 | 52.93 |
Female | 337,076 | 47.07 |
Immigration status | ||
Resident children | 335,120 | 46.79 |
Migrant children | 380,338 | 53.11 |
Foreign children | 720 | 0.10 |
Urbanicity | ||
Inner | 396,782 | 55.40 |
Outer | 319,396 | 44.60 |
Birth year | ||
2012 | 102,425 | 14.30 |
2013 | 95,979 | 13.40 |
2014 | 107,674 | 15.03 |
2015 | 97,433 | 13.60 |
2016 | 111,492 | 15.57 |
2017 | 105,894 | 14.79 |
2018 | 95,281 | 13.30 |
Socioeconomic level of resident areas | ||
High | 258,474 | 36.09 |
Low | 457,704 | 63.91 |
Scale of immunization clinics | ||
Large-scaled | 313,599 | 43.79 |
Midsized | 180,796 | 25.24 |
Small-sized | 221,783 | 30.97 |