The majority of caregivers of left-behind children in rural China are their mothers and grandmothers. The mental health of children's caregivers is one of the significant factors affecting the early development of children. Currently, there is a lack of research and comparison on the factors influencing depression among mothers and grandmothers of left-behind children in rural China.

To investigate the determinants of depression among female caregivers of left-behind children in rural China.

Data were collected from the baseline survey of the Home Visit Intervention Evaluation Segment of the Health and Development Promotion Program for Left-behind Children, conducted by UNICEF from April to July in 2018. The villages were selected through multi-stage stratified sampling. 1 or 2 towns were chosen as program towns in each of the 5 impoverished counties in 5 provinces. Villages in program towns were stratified by number of under-3-year-old children except Pingshan, where all villages from the program town were included. Three villages were randomly selected in each stratum as intervention villages, matched with control villages of similar number of under-3-year-old children, socioeconomic status and the distance from county. Ultimately 113 villages in 27 towns were included in the survey. This study focused on the mothers and grandmothers of left-behind children under 3. Questionnaire was used to collect the data of left-behind children under 3 years old and their main caregivers participating in the survey, and Zung Self-rating Depression Scale (ZSDS) was used to assess the depression status of caregivers. Multivariate Logistic regression was used to analyze the determinants of depression in the main caregivers of left-behind children.

A total of 728 subjects were included in this study, including 282 mothers and 446 grandmothers. The overall incidence of depressive symptoms was 32.8% (239/728) . The prevalence of depression among mothers and grandmothers of left-behind children was 29.8% (84/282) and 34.8% (115/446) respectively, with no statistical significance between two groups (P>0.05) . Multivariate Logistic analysis revealed that for mothers, caring for 1-year-old children (OR=2.041, 95%CI=1.065-3.913) , 2-3-year-old children (OR=2.128, 95%CI=1.023-4.425) , and experiencing caregiving stress (OR=4.043, 95%CI=2.152-7.594) were risk factors for depression (P<0.05) . A mean communication time ≥10 minutes per time with absent fathers (OR=0.396, 95%CI=0.175-0.898) was a protective factor against maternal depression (P<0.05) . For grandmothers, looking after girls rather than boys (OR=0.506, 95%CI=0.331-0.772) was a protective factor for depression (P<0.05) . Conversely, being 60 years or older (OR=1.879, 95%CI=1.082-3.261) , self-rated health status affecting caregiving (OR=2.402, 95%CI=1.364-4.231) and children's mothers cumulative longer absence from home (OR=2.468, 95%CI=1.059-5.751) were the risk factors for depression (P<0.05) .

The incidence of depression among female caregivers of left-behind children in rural China is high. Mothers and grandmothers, as the primary caregivers of most left-behind children, experience different factors affecting depression. Older children, high caregiving stress are risk factors for maternal depression, whereas greater communication with the children's fathers is protective factor for maternal depression. Grandmothers face a higher risk of depression when advanced age, self-report health status affacts caregiving, and children's mothers are absent from home for extended period, while caring for a granddaughter is a protective factor against grandmother's depression.