Table 2.
Main outcomes (only statistically significant outcomes provided).
| Group | Outcome (Left-Behind Children) | Sample Size (N) | Covariates 2 | Statistics (OR, Mean, SD, p, 95% CI or Other Statistics If Provided) 1 | Reference |
|---|---|---|---|---|---|
| Internal Migration | |||||
| Physical Health | More susceptible to illness | 735 | Parenting styles, age of child, health literacy | OR 1.628, p < 0.05 | Mo, 2015 [35] |
| Childhood illness | 8662 | Age, gender, household size, income per capita, grandparents living together, village context, village size | OR 1.29, SE = 0.164, p < 0.05 | Tong, 2015 [42] | |
| Pre-hypertension or hypertension | 2170 | Age, gender, mothers education, fathers education, annual household per capita income | OR 7.77, 95% CI 2.05–29.4, p < 0.01 | Wen, 2016 [43] | |
| Nutrition, Weight and Height | Lower Height for age z-score | 5413 | Age, gender | OR −0.165, p < 0.01 | Lei, 2018 [32] |
| Lower Weight for age z-score | 5413 | Age, gender | OR −0.142, p < 0.05 | Lei, 2018 [32] | |
| Malnutrition rate | 827 | NR/NA | LBC 14.83%, NoN-LBC 7.04%, p < 0.01 | Tao, 2016 [40] | |
| Less likely to be ever breastfed | 6136 | Age, gender, ethnicity, elder siblings, guardian education attainment, the number of household electrical appliances, year of survey | OR 0.30, 95% CI 0.17–0.52 | Ban, 2017 [26] | |
| Less likely to be breastfed | 1548 | NR/NA | LBC (78.7%), Non-LBC (82.8%), p < 0.05 | Luo, 2008 [34] | |
| Shorter breastfeeding | 6136 | Age, gender, ethnicity, elder siblings, guardian education attainment, the number of household electrical appliances, year of survey | β-3.77, 95% CI −5.01–−2.53 | Ban, 2017 [26] | |
| Duration of breastfeeding (months) | 1548 | NR/NA | LBC M = 9.48, SD = 3.58; Non-LBC M = 10.70, SD = +3.26; p < 0.001 | Luo, 2008 [34] | |
| Unhealthy behaviors | Alcohol use | 1367 | Gender, age, grade, if only child in the family, perceived school performance | OR 2.01, 95% CI 1.28–3.16, p < 0.05 | Jiang, 2015 [31] |
| Higher smoking rate | 1343 | Gender, grade, if only child in the family, perceived school performance | OR 5.59, 95% CI 2.38–13.15, p < 0.001 | Yang, 2016 [44] | |
| Injuries | More likely to experience injury | 4479 | Gender, age, fair physical health, school academic achievement, only child in the family, household income level, parental marital status; maternal education attainment, family conflicts; model school; peer rejection, rural region | OR 1.208, SE 0.104, p < 0.05 | Hu, 2018 [30] |
| Higher injury rate | 3019 | NR/NA | LBC 252.9/1000, 95% CI 233.0–273.0, Non-LBC 119.7/1000, 95% CI 104.9–134.7, p < 0.0001 | Shen, 2009 [37] | |
| Immunization | Lower rates of timely vaccination | 1216 | NR/NA | LBC55.7%, 95% CI 51.3–60.0, Non-LBC 60.8, 95% CI 57.3–64.0, p = 0.011 | Tang, 2016 [39] |
| Less likely to receive complete vaccination | 1368 | NR/NA | LBC 92.7%, Non-LBC 79.9%, X2 = 35.2, p < 0.001 | Ni, 2017 [36] | |
| Lower coverage of complete vaccination | 1662 | NR/NA | LBC 38.7%, Non-LBC 44.2%, p < 0.036 | Tang, 2019 [38] | |
| International Migration | |||||
| Physical Health | Maternal reported child poor health | 542 | Data from model with no covariates added | OR 0.33, 95% CI 0.16–0.7, p < 0.01 | Edelblute, 2018 [17] |
| Poorer physical health | 205 | NR/NA | LBC M = 5.09, SD = 0.78; NoN LBC M = 5.43, SD = 0.63; F (1.199) = 9.08; p < 0.01 | Smeekens, 2012 [21] | |
| Unhealthy behaviors | Lower physical activity | 239 | Age, gender, body mass index, maternal schooling, paternal schooling, household characteristics | OR −0.56, p < 0.05 | Palos-Lucio, 2015 [18] |
1 LBC, left-behind children; Non-LBC, not left-behind children; 2 NR/NA, not reported or not applicable.