As the population ages, China's elderly care services are developing rapidly, but there is a structural contradiction between the strong demand for elderly care and the labor shortage in nursing homes. Only women from the middle and lower class prefer to provide nursing care and serve the function of ‘human infrastructure’ to the elderly service system, whose moral connotation and social effects have been recognized, but the professional skills and market value are not.1 Most of them have an education level of junior high school or below, and lack formal nursing training, thus their average income and welfare are lower than other care workers such as maternity matrons and usually lack the protection of labor rights, while their workload and content are heavier and more trivial, with long and frequent time to care for the disabled elderly. Overall, caregivers in Chinese nursing homes can be characterized by ‘low social status, low income, low educational level’, and ‘high mobility, high labor intensity, high average age’, which have already caused the problem of low work engagement and high turnover intentions.

Work engagement is a positive, continuous, and complete emotional and cognitive state of work characterized by vigor, dedication, and absorption.2 Studies have shown that work engagement is a crucial factor in improving nursing performance,3 and has a significant impact on the quality of services, while some internal and external factors are antecedent variables that affect work engagement: (1) income and welfare satisfaction. Income and welfare are two different kinds of payments for work, with income being one's direct compensation (e.g., wage or salary) and welfare being one's indirect pay (e.g., insurance, pensions, income maintenance, and miscellaneous services).4 whose satisfaction is determined by the correspondence between what is received and what should receive.5 The low income-welfare satisfaction of caregivers in nursing homes tends to trigger their frequent departure and turnover, which can reduce the quality of elderly care services directly.6 (2) Competency. Competency refers to the knowledge, skills and internal psychological structures (e.g., self-concept, traits, or motivation) required for an individual to achieve organizational goals.7 Although caregivers may be diligent, due to their low literacy and professionalism, they are physically, energetically and skillfully difficult to perform delicate care work, which limits the capacity and engagement of care services. (3) Professional identity. Professional identity refers to how individuals perceive themselves as professionals, which includes their professional interests, values, identifications, and ambitions.8 Caregiving for elderly individuals is generally considered an indecent job by society due to their low social status and identity, and this social prejudice about the profession can affect their work status and care quality in some way.9 (4) Family support. Family support refers to how much individuals feel that their family members care, comprehend, and provide emotional and material support for their work, and they acknowledge their contribution. Lack of social support and family communication and understanding can easily lead to dissatisfaction, work passivity and even the resignation of caregivers.10

Therefore, to enhance the work engagement of caregivers in nursing homes, it would be necessary and meaningful to study the association among income-welfare satisfaction, competency, professional identity, and work engagement. Based on the 1212 survey data of nursing home caregivers in China, we first investigated the effects of income-welfare satisfaction and competency on work engagement through the structural equation. Then we tested the mediating effects using the Sobel test, Bootstrap method, and Monte Carlo, and analyzed the mechanism of professional identity under the above effects. Finally, we tested the moderating role of family support on the mediating effects.