The in�uence of medical insurance and social security cards on the �oating population's settlement intention

Abstract


Introduction
Under the household registration system of China, the oating population is de ned as those whose registered permanent residence is in the original residence, and who live and work in the current residence with separation from registered permanent residence (1)(2)(3). According to < China Statistic Almanac> (2019), the oating population was 244 million in 2017 and 241 million in 2018 (4).The "Statistical Bulletin of National Economic and Social Development 2019" released by the National Bureau of Statistics declare that there is 236 million oating population in 2019 (5). According to this situation, the oating population in the future will maintain this considerable volume. (6). Settlement intention is de ned as the thoughts of the oating population about future relocation arrangements after they have been in their current residence for some time. Nowadays, there exist differences in social welfare and public service treatment between the oating population and residents. To effectively promote the social integration between them, improve the oating population's settlement intention, further accelerate the urbanization process, promote economic development, it is of certain practical signi cance to discuss the oating population's settlement intention and its in uencing factors.
It has been shown that the individual characteristics of the oating population, the characteristics of the place of origin and current residence all in uence the oating population's settlement intention, such as whether to purchase urban housing and housing conditions (7,8), family migration (9), environment and regional differences (10,11);, education level, work status, social integration(2),etc. However, little attention has been paid to the impact of the basic medical insurance of urban employees (UEBMI) and social security cards on the oating population's settlement intention. Researchers have demonstrated that participating in UEBMI and applying for social security cards can improve the happiness of the oating population and further enhance their willingness to settle. Therefore, the research idea of this article is to use the survey data of China's oating population dynamic monitoring in 2017 (Volume A), apply binary logistic regression and structural equation model to analyze the in uence of UEBMI and social security cards on the oating population's settlement intention. To examine the comprehensive causal relationships, "social integration" is introduced as a mediator variable. Therefore, this paper answers the following research questions: 1. What effect do UEBMI and social security cards have on settlement intention? 2. Will UEBMI and social security cards affect the oating population's settlement intention through social integration?
The remainder of the paper is as follows: The second section reviews the literature on migration theory and the role of UEBMI and social security cards. The third section introduces the data source, assignment, and research methods. The fourth section gives the results of binary logistic regression and structural equation model. The fth section analyzes the above results. The last section gives conclusions and provides recommendations for the government.

Theoretical framework
The most widely used migration theory is the push-pull theory, which originated in the 19th century. E. G. Ravenstein rst analyzed population migration and proposed the "seven laws" of population migration.
Later, Rudolph Heberle proposed in the "The causes of rural-urban migration a survey of german theories ", push and pressure were the most important factors affecting the ow (12). D.J. Bague rst proposed the "push-pull theory" in the study of the reasons for the oating population. He believed that improving living standards were the purpose of the oating population. The factor that owed out of the place of origin to improve living standards was the thrust, while the factor that owed into the current residence was the pull (13). Combined with previous researches, the American scholar E.S. Lee proposed a systematic population migration theory in the 1960s-push-pull theory, the factors of oating population migration for the rst time were divided into two categories, namely, push and pull, and the push was negative factors and pull was positive factors, both of which jointly affected the migration willingness of migrants (14).
Given the fact that many factors are impacting the oating population's settlement intention, combining the push-pull theory and existing researches, researches classify these factors into four categories: in ow factors, out ow factors, barriers between in ow and out ow areas, and the oating population's selffactors (15).

The importance of UEBMI and social security cards
Medical insurance is a social insurance system that prevents workers from becoming too economically burdened due to illness. UEBMI is a social medical insurance system that guarantees employees' basic medical rights according to law. It enforces through laws and regulations. Implement the basic mode that the society plans as a whole medical treatment fund and individual medical treatment account union. After paying a certain period, you will enjoy medical insurance reimbursement for life. On the one hand, UEBMI is the government's means of realizing income redistribution and promoting social equity. On the other hand, it is also a guarantee of maintaining social stability, alleviating the worries of sick workers, and working with peace of mind.
Social security cards are electronic certi cates for workers to work in the eld of labor security. There are two types: urban employee social security card and resident social security card. They can verify the identity of the patient when purchasing medicine or medical treatment, store personal account funds, and record the medical consumption of the insured. The setting of UEBMI and social security cards in the current residence plays an important role in the settlement intention of the oating population.
Study on the in uence of medical insurance on the settlement intention of oating population Medical insurance, as a way of obtaining economic compensation in case of illness or accident, profoundly affects the quality of life of the oating population. However, the long-term marginalization of the oating population in their current residence and the di culty in securing public services and the right to health have led them to be cautious in deciding whether to settle in current residence in the future. Therefore, the research on the in uence of medical insurance on the oating population's settlement intention has received increasing attention from the academic community and policymakers in recent years. The current residence provides medical insurance for the oating population in the new environment will improve the stability of their life and work prominently.
(16, 17). Studies have shown that different regions participate in medical insurance situation is different, and the older, the higher the education level, the higher the income, the children living in the place of arrival, and the poor health status of the oating population has a higher willingness to participate in medical insurance (18). The oating population participating in the new rural cooperative medical insurance need to return to their hometown because they cannot reimburse the medical expenses in the current residence, while the oating population participating in UEBMI can be directly reimbursed by a higher proportion., so they are more willing to settle down in the current residence (19,20).

Data sources
The data was based on the survey data of China's oating population dynamic monitoring which was collected from the annual large-scale national oating population of 31 provinces(autonomous regions and municipalities) and the Xinjiang Production and Construction Corps by the National Health Commission since 2009,where the oating population is relatively concentrated in ow place (21), After dealing with the missing values of some variables, a total of 154586 subjects were included in this study.

Variables and measurements
The core independent variables of this article were UEBMI and social security cards, including whether to participate in urban employee basic medical insurance and whether to apply for personal social security cards. The dependent variable was the settlement intention. It was measured by whether you are willing to move your household registration to the current residence. The mediator variable was social integration, expressed as Do you agree that I think the locals are willing to accept me as a member.
The control variables included four categories: (a) demographic characteristics (i.e., age, gender, marital status, the household registration system, and education level), (b) economic characteristics (i.e., average monthly total local expenditure over the past year and whether to sign a labor contract), (c) owing characteristics (i.e., owing range and owing time),(d) health education (i.e., whether to receive health education on occupational disease prevention, whether to receive health education on STD and AIDS prevention, whether to receive health education in the prevention and treatment of chronic diseases.). All of the variables are presented and described in Table 1.

Research Methods
Firstly, we analyzed the in uence of UEBMI, social security cards, and social integration on settlement intention by controlling the above characteristic variables, with binary logistic regression method. Then considering the results of single-factor analysis and binary logistic regression analysis, the variables with statistical signi cance were included in the structural equation model.
In this paper, we used the structural equation modeling software Amos 22.0, and the classical bootstrapping method to estimate the direct and indirect effects of core independent variables (22)(23)(24). It is effective to solve the measurement errors of variables and examine related risk factors. Meanwhile, it also provided direction for interventions (25,26) .Compared with the proven model tting standards (27)(28)(29), this model was more suitable for our paper, the results have been presented in Table 2.

Descriptive analysis
According to Table 1, 39.9 percent of the oating population expressed their willingness to move their household registration system into the local area and settle there. This result is similar to previous research (30). Of these respondents, about 77.7 percent do not participate in UEBMI, and 50.5 percent of the oating population has applied for personal social security cards. Besides, the survey found that the oating population had good social integration in the current residence (93.7 percent).
Regarding demographic characteristics, majority of respondents are rural residents, married, young, and middle-aged men (95.2 percent), and nearly 43.5 percent of the respondents stopped at junior high school. Besides, 51.5 percent of the oating population is within the province, and the migration time is less than 8 years. Nearly 58 percent of them have signed labor contracts, and the average monthly expenditure in the past year was 1,000-3,000 yuan. In terms of health education, the oating population received the most health education on STD and AIDS prevention, but the overall acceptance of health education was poor.
UEBMI, social security cards, social integration, and settlement intention Taking settlement intention as the dependent variable, we analyzed the in uence of UEBMI, social security cards, and social integration on settlement intention by binary logistic regression, controlling the above four types of variables. The results are presented in Table 3. As Table 3 shows participating in UEBMI in uences the oating population's settlement intention. Speci cally, the oating population's settlement intention on participating in UEBMI is 23.2 percent higher than those who did not participate. And during the single factor analysis, it found that whether to apply for personal social security cards is related to the settlement intention. Moreover, when asked do you agree that I think the local is willing to accept me as a member, the proportion of the oating population agreeing to settle down was 2.026 times that of the oating population disagreeing. It is demonstrated that social integration has a positive impact on the settlement intention of the oating population.

The mediating effect of social integration
Mediation analysis is an important tool for statisticians to study causality. The essence is to study whether or to what extent the independent variable acts on the dependent variable by affecting the mediator variable and clarify the direct effect, indirect effect, and total effect (22,31). Based on the above results, we conclude that UEBMI, social security cards, and social integration have positive impact on settlement intention. To further clarify the causal relationship, we analyzed the intermediary effect by bootstrapping method. And then we incorporated some in uencing factors into the structural equation model to form three dimensions: social insurance and security, social integration, and settlement intention. Reliability is 0.600, 0.804, 0.823, and the validity is 0.500, 0.695, 0.719, respectively. The tness index (GFI/AGFI/CFI) are all greater than 0.9, and the RMSEA is less than 0.05. Even though the reliability and validity of social insurance and security are slightly lower, the overall t of the model is appropriate, and the values in Table 4 are positive, which indicating that each variable is statistically signi cant. Therefore, the structural equation model is shown in Fig. 1. According to the model results, the standardized regression coe cients among social insurance and security, social integration, and settlement intention are positive values, and the factor loading coe cient of each observed variable is greater than 0.5. The results of the mediation effect using the bootstrapping method present in Table 5. It is found that the Z values of the overall effect, indirect effect, and direct effect are all greater than 1.96, and the con dence interval of the indirect effect does not include 0, indicating that both direct and indirect effects exist in this model. This model is a partial intermediary, with an intermediary ratio of 10.66 percent.  (32),and participation in UEBMI has a greater in uence on settlement intention than participation in other types of insurance (20). This result could attribute to UEBMI only needs to pay a certain number of years to enjoy medical insurance reimbursement for life. Besides, on the one hand, the employer and the individual jointly pay UEBMI, the employer pays more than an individual, and the reimbursement rate of medical insurance is higher. On the other hand, participating in UEBMI can improve the risk resistance of the oating population in the current residence, reduce the cost of living and reduce the economic burden to a certain extent (33)(34)(35) .The balance in the personal account not only for the settlement of outpatient and hospital expenses but also to buy drugs at designated pharmacies. UEBMI is a factor that affects the settlement intention (36), which is consistent with the results of this study.
When it comes to social security cards, although it has an impact on settlement intention in univariate analysis and not in regression analysis, previous studies have shown that social security cards, as the embodiment of social security services, plays an important role in the fairness of the whole society.
Social security cards are divided into urban employee social security card and resident social security card. As long as the urban employees participate in the UEBMI, they will get the urban employee social security card. If an accident occurs, the urban employee can use the social security card to reimburse the hospitalization expenses at a higher rate locally. The resident social security card is to participate in the urban resident basic medical insurance and the new rural cooperative medical scheme. Although there is no balance to consume at the time of medical treatment, it is a certi cate of reimbursement when the patient discharge from the hospital. Therefore, the social security card is an important guarantee for the oating population to integrate into their current residence and live a stable life, which nally includes the analysis. This is also consistent with previous research results (37,38) .
The in uence of UEBMI and social security cards on the oating population's settlement intention also re ected in the research on household registration. Although the household registration system has always considered as a hinder to the settlement of migrants in the current residence, recent studies have shown that the household registration system has little or no signi cant effect on the oating population's settlement intention (8,36,39,40). What affects the oating population's settlement intention is a series of services and rights brought by the household registration system. This is also the reason why the oating population chooses to live in two places. Accordingly, the oating population wants to live in the current place for a long time to settle down, must attend insurance actively, deal with social security cards.
This paper proves that social integration will promote the settlement intention of the oating population.
This is because the migrating population who handles their social relations well will promote their career development, improve their quality of life, and ultimately improve their life satisfaction in the current residence. At the same time, the residents are willing to accept the oating population as a member, which re ects the harmonious social relationship between them, which is consistent with the research of Chen, Shaowei, Huang, Xu (41,42).

The mediating effect of social integration
The above results have demonstrated that UEBMI, social security cards and social integration have a positive impact on the settlement intention of oating population. At the same time, some studies also show that the participation of oating population in medical insurance that re ects social security in their current residence will have a positive impact on social integration, and the better the social integration, the more behaviors of participating in medical insurance. That's because health insurance can increase the security of a population where it lives. Therefore, we analyzed the causal relationship further by structural equation model, with social integration as mediator variable. The structural equation model proves that UEBMI and social security cards have positive in uence on social integration and settlement intention, and at the same time, social integration also has a positive effect on settlement intention. This is because participating in UEBMI and getting a personal social security cards can help solve some of the accidents that happen to oating population in their place of residence. Without too much consideration of economic pressure, they can improve the quality of life through hospitalization for injuries and illnesses, and nally improve the utilization level of health services for oating population. It is reasonable to infer that settlement intention will be stronger with the improvement of oating population conditions.
We have explained the issues raised in the introduction: UEBMI, social security cards, and social integration have a positive impact on settlement intention, and will indirectly affect the settlement intention through social integration. Even if this in uence is little, it will still be helpful to our policy formulation to further strengthen the oating population's settlement intention in the current residence, advance the urbanization process, and promote economic development. However, this study also has some limitations. The result of this study is the mining of existing data. Due to the limited variables in the original data, the reliability of some indicators and the intermediary ratio is low. If one can add new effective variables in the future, the explanation of the in uence of medical insurance and social security cards on settlement intention of the oating population will be more complete.

Conclusions
The oating population has tremendous implications for urban economic growth, and their settlement intention in the current residence directly affects the development of there. With the development of health services, population aging, chronic diseases, infectious diseases, and public health emergencies increase, the health and quality of life of the oating population pay more and more attention. Therefore, it is necessary to study the in uence of UEBMI and personal social security cards on the settlement intention. The results concluded that the oating population participates in UEBMI locally, and applying for a personal social security cards improve settlement intention directly in the future, and it will also have a positive in uence through social integration. This indirect in uence is little, but it provides us with a valuable solution in promoting the integration of the oating population and residents. In 2014, the Chinese government proposed a "people-oriented urbanization" policy (43),consequently, to attract migrants to settle down, the government should strengthen the management of the social insurance system for the oating population, improve the transfer of the insurance system in different regions, and simplify the procedures for the medical treatment in different places. And the government should increase the possibility of migrants participating in insurance in other places and effectively accelerating the urbanization process.

Declarations
Ethics approval and consent to participate The study protocol was approved by Ethics Committee of Biomedical Research, Henan University. The committee's reference number: HUSOM2020-267.

Consent for publication
The data used in this article is public.
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