Introduction

According to the second China National Sample Survey on Disability (CNSSD), it is estimated that by the end of 2010, the total number of people with disabilities in China had reached 8.52 million(Zhao, 2012). At the final stage of the “13th Five-Year Plan” on building a moderately prosperous society in all respects (Zhou, 2017), whether people with disabilities are physically and mentally healthy, whether their families are happy, and whether their lives are generally decent, are important indicators for measuring whether China can build a moderately prosperous society in all respects. Furthermore, the Central Committee of the Communist Party of China and the State Council issued the Healthy China 2030 Plan Outline, which states that health is a must for promoting well-rounded personal development and a prerequisite for social and economic development, which proposes that the gaps in health services and conditions between different localities and between different groups should be narrowed, and which requires that China should formulate and implement the health intervention plan for special groups including people with disabilities (Zhao, 2012). With the continuous development of contemporary medicine and positive psychology, people no longer only focus on physical health, but they have begun to pay more attention to mental health. People with disabilities are a social group with special difficulties due to their physical disabilities and functional impairment (Zheng, 2008), and their mental health issues have gradually become a spotlight of researchers’ attention. According to the data of the 2013 Monitoring Report on the Status and Progress towards a Comfortable Life of Persons with Disabilities in China, people with disabilities rarely participated in community cultural and sporting activities, and nearly two-thirds of people with disabilities had not really gone out of their homes and integrated into society (Chen et al., 2014). It can be seen from this that social avoidance is a common problem currently faced by people with disabilities in China, and it may even gradually affect their physical and mental health.

Social interaction is an essential part of people’s social activities. “Social avoidance” refers to an individual’s tendency to avoid participating in social activities, which is manifested as refusing to be with others, refusing to talk, or even avoiding everyone for certain reasons; social distress refers to the absence of positive emotional experiences experienced in social interaction(Wright et al., 2012). Previous studies have shown that most people with disabilities tend to self-impose isolation and avoid socializing with others in their behaviors (Ye & Zhang, 2010). Compared with healthy people, people with disabilities generally have poor mental health, they are plagued by emotional problems such as loneliness, social anxiety, and inferiority, and some of them whose mental health are severely challenged even have the idea of committing suicide (Yan, 2013). Social avoidance and distress frequently haunt people with disabilities, and gradually cause them to separate from mainstream social groups and become marginalized when interacting with peers, which have affected their normal socializing, learning, rehabilitation, and development (Liao & Zhang, 2013). Based on this, it is extremely important to explore the impacting factors and the mechanism of social avoidance and distress among people with disabilities, with the goal of helping the social reintegration of people with disabilities.

Impacts of family functioning on social avoidance and distress

Unlike healthy people, people with disabilities are limited by their own functions, and the family is the main place of their daily life. In addition, under the social conditions that China’s social welfare system is not yet perfect, the life stress of people with disabilities is mainly borne by their family members, and their dependence on the family is stronger than that of healthy people. Previous studies have also shown that: firstly, in terms of economy, only 27.42% of the 34 million people with disabilities of working age in China have the ability to work, while the employment rate of people with disabilities who with the ability to work is only about 40% (Huang, 2006), so the most important source of income for most people with disabilities is the support from their family members; secondly, in terms of medical rehabilitation, due to reasons such as the current imperfect social welfare system in China, most people with disabilities cannot have access to adequate medical rehabilitation services and life care from the society, which they can only obtain from their families; thirdly, in terms of mental health, the family is the main place for people with disabilities to live their daily life and communicate with the outside world. The attitudes of family members would directly affect the emotional state and happiness of people with disabilities(Zhao, 2014). The functions of family played in the physical and mental development of people with disabilities have gradually become a spotlight of researchers’ attention.

The concept “Family Functioning” was first proposed in the 1970s. At that time, McMaster proposed a model based on systems theory, the crucial assumptions of systems theory which underlie the model are as follows: (1) All parts of the family are interrelated; (2) One part of the family cannot be understood in isolation from the rest of the family system; (3) Family functioning cannot be fully understood by simply understanding each of the individual family members or subgroups; (4) A family’s structure and organization are important factors that strongly influence and determine the behaviour of family members; (5) The transactional patterns of the family system strongly shape the behaviour of family members(Miller et al., 2010). Currently, the concepts on family functioning are mainly divided into two orientations: one is to pay attention to the results of family functions, such as Beavers, Olson, and Sheik et al., while the other is to emphasize the process of developing family functions, such as Epstein and Skinner et al. Beavers focuses on describing family functioning from the aspects of intimacy, connection quality, and family adaptability among family members(Beavers & Hampson, 2000). On this basis, connecting with Chinese local culture, Sheik proposes to define family functioning by the lifestyle and quality on the two-way relationships between husband and wife and between parents and children within the family system (Sheik, 2002). Olson argues that family functioning is the effectiveness reflected in the communication, emotional connection, family rules and coping with external stressful events among members within the family system(Olson, 2002). Skinner propose that families fulfill their functions by meeting the physical and mental growth and self-development needs of members within the system (Skinner & Stein Auer, 2000). From the perspective of either the results-oriented or process-oriented family functioning theory, relevant empirical studies have shown that the better the family functions are played, the higher the level of individual mental health is. Family functioning can effectively reduce the level of social avoidance and distress (Xia et al., 2022).

However, it is far from enough to only examine the direct relationships among variables. It is necessary to further discuss the internal mechanism by which family functioning affects social avoidance and distress on the basis of previous studies. Exploring the mediating effect is conducive to clarifying how family functioning affects social avoidance and distress. Studying the moderating effect is conducive to defining when such effect works. Studying the mediation with moderation can reveal whether the mediating process is moderated by the moderating variable, and can answer “how” the independent variable affects the dependent variable and “when” such effect is stronger or weaker(Wen et al., 2012).

Effectiveness of perceived social support and happiness

On the basis of literature review, this study argues that perceived social support and happiness may be important mediating variables in the impact of family functioning on social avoidance and distress.“Perceived social support” refers to the individual’s emotional experience and satisfaction with being respected, supported and understood in society (Sarason et al., 1991), which is an important factor affecting the social interactions of people with disabilities. In many studies on social avoidance and distress, researchers have always attached great importance to the impact of perceived social support on social avoidance and distress, and the individuals with a stronger perceived social support propensity have a lower level of social avoidance and distress (Wang, 2007). Furthermore, from the perspective of the meaning of the dimensions of family functioning, problem solving, communication, roles, affective responsiveness, affective involvement and behavior control are the individuals’ evaluation and experience of their family functioning. The better people with disabilities evaluate these factors, the more understanding, respect and support they get in the family, that is, the higher the level of their perceived social support is. To sum up, the people with disabilities with a higher level of family functioning also have a relatively higher level of perceived social support, thus reducing their social avoidance and distress. Therefore, this study proposes hypothesis 1: perceived social support is a mediating variable between family functioning and social avoidance and distress among people with disabilities.

Happiness, which comprehensively evaluates an individual’s quality of life based on certain criteria, is an important psychological indicator reflecting the individual’s quality of life. Numerous studies at home and abroad have shown that happiness can effectively predict an individual’s level of mental health. The individuals with a higher level of happiness are more willing to participate in social activities such as physical exercise (Chen & Wang, 2012), thereby effectively reducing the level of social avoidance and distress. Furthermore, empirical studies have also revealed that the most important factors affecting an individual’s happiness are the individual’s marital affection and his/her relationships with his/her children and other people (Wong & Yuen, 2023). In other words, the emotional state of family members is the most important factor affecting an individual’s happiness. To sum up, the people with disabilities with a higher level of family functioning also have a relatively higher level of happiness, thus reducing their social avoidance and distress. Therefore, this study proposes hypothesis 2: happiness is also a mediating variable between family functioning and social avoidance and distress among people with disabilities.

Although perceived social support and happiness may have impacts on social avoidance and distress, there may be some differences in the impacts. Therefore, it is necessary to examine whether these two mediating processes are impacted by other variables. Considering that people with disabilities with the same level of perceived social support may have different levels of social avoidance and distress, it is necessary to examine whether there are other variables that moderate the relationship between perceived social support and social avoidance and distress.

Effectiveness of self-esteem

Self-esteem is an individual’s evaluation of his/her own emotions. It is the core component of oneself and the core concept of the sense of self-worth in personality characteristics, which affects the way the individual responds to the surrounding environment(Kernis, 2003). With the increase in studies on mental health of people with disabilities, more and more attention has been paid to the role of self-esteem in mental health of people with disabilities. A high level of self-esteem not only has a positive effect on the individuals’ mental health, but also has an important impact on their positive cognition, motivation, emotions, and social behaviors, etc. In interpersonal encounters, the individual with a higher level of self-esteem has positive social behaviors, while the individual with a lower level of self-esteem is prone to social anxiety experience and social avoidance behavior (Hong & Song, 2014). Previous studies have shown that due to their own physical functional impairments, people with disabilities are accordingly hampered in their daily lives, affecting the establishment of their high self-esteem level(Li & Liu, 2018). As a result, people with disabilities are often subject to negative social evaluation and feedback, which is manifested as negative attention bias (Dandeneau & Baldwin, 2009). In other words, they would think that society does not provide adequate support for them, causing their socializing adaptability to decline rapidly (Yao et al., 2010). Therefore, for the people with disabilities with a low level of self-esteem, their perceived social support may lose the capability of resisting risks. At this time, regardless of the level of their perceived social support, their social avoidance and distress would be high.

So far, few studies have examined whether self-esteem can moderate the relationships (including direct or indirect relationships) between happiness and social avoidance and distress, and what is the specific model of such moderating effect. Considering that currently there is still a lack of research evidence, this study only analyzes the moderating effect of self-esteem on perceived social support. Moreover, considering that the few existing studies mostly involve whether the second half section of the mediation chain is moderated by self-esteem, this study is also exploratory in analyzing whether the first half section of the mediation chain and the direct effect are moderated. On this basis, this study proposes hypothesis 3: self-esteem moderates the mediating effect of perceived social support.

In summary, this study mainly covers two areas: (1) exploring whether perceived social support and happiness have mediating effects on the relationship between family functioning and social avoidance and distress; (2) examining whether self-esteem moderates this mediating effect, that is, whether the mediating process of family functioning on social avoidance and distress through perceived social support is moderated by the variable “self-esteem”. This study focuses on whether self-esteem moderates the latter half path of this process. Figure 1 is a hypothesis model of this study, which describes the research variables and hypotheses to be tested in this paper.

Fig. 1
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The moderated mediation hypothesis model

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Methods

Subjects

The respondents for this study were 600 people with disabilities and 600 healthy people selected through convenient sampling from all municipal districts, counties, towns and villages in Henan Province. After eliminating invalid questionnaires, a total of 406 valid questionnaires on people with disabilities were recovered, with a valid recovery rate of 67.7%; these people with disabilities included 251 men and 155 women (40 persons under the age of 16, 315 persons aged 15–59, and 51 persons aged 60 and above; 15 persons lived in the provincial capital city, 182 persons in municipal districts and county towns, 87 persons in townships, and 122 persons in villages). A total of 447 valid questionnaires on healthy people were recovered, with a valid recovery rate of 76.2%; these healthy people included 253 men and 194 women (82 persons under the age of 16, 310 persons aged 15–59, and 55 persons aged 60 and above; 24 persons lived in the provincial capital city, 194 persons in municipal districts and county towns, 87 persons in townships, and 142 persons in villages).

Instruments

Family assessment device (FAD)

This study employs the Chinese version of FAD prepared by Miller et al. (Lv & Zhou, 2023) based on the theory of the McMaster Model (Miller et al., 2010) of Family Functioning. The FAD consists of seven subscales (problem solving, communication, roles, affective responsiveness, affective involvement, behavior control, and general functioning), with a total of 60 items, and it uses the four-point scale. After summarizing the scores of 60 items, the higher the total score is, the stronger the family functioning is. In this research, the result of reliability test shows that the Cronbach’s α of the FAD is 0.81.

Perceived social support scale (PSSS)

This study employs the Chinese version of PSSS (Guo et al., 2023) prepared by Blumenthal and Zimet et al. (Blumenthal et al., 1987). The PSSS consists of 12 self-assessment items, which are divided into the support from family, support from friends, and support from significant other. After summarizing the scores of 12 items, the higher the score is, the higher the level of perceived social support is. In this research, the result of reliability test shows that the Cronbach’s α of the PSSS is 0.89.

Memorial university of newfoundland scale of happiness (MUNSH)

This study employs the Chinese version of MUNSH (Xu et al., 2021) prepared by Kozma and Stones (Kozma & Stones, 1980), and revises its items descriptively so that it can be used as instrument for measure the happiness of people with disabilities. The MUNSH consists of 24 items, including 5 items reflecting positive affect (PA), 5 items reflecting negative affect (NA), 7 items reflecting general positive experience (PE), and 7 items reflecting general negative experience (NE). The composite happiness score = PA-NA + PE-NE. The higher the score is, the higher the level of Happiness is. In this research, the result of reliability test shows that the Cronbach’s α of the MUNSH is 0.77.

The self-esteem scale (SES)

This study employs the Chinese version of SES (Gao & Zhang, 2018) prepared by Rosenberg (Rosenberg, 1965). The SES consists of 10 items, and it uses the four-point scale. After summarizing the scores of 10 items, the higher the total score is, the stronger the self-esteem is. In this research, the result of reliability test shows that the Cronbach’s α of the SES is 0.73.

Social avoidance and distress scale (SAD)

This study employs the Chinese version of Social Avoidance and Distress Scale (SAD) prepared by Watson and Friend and revised by Ma Hong (Wang, 1999). The SAD consists of 28 items, adopting the “true/false” scoring system. Of all items, 14 items are used to evaluate social avoidance, while the remaining 14 items are used to evaluate social distress. After summarizing the scores of 28 items, the higher the score is, the higher the level of social avoidance and distress is. In this research, the result of reliability test shows that the Cronbach’s α of the SAD is 0.74.

Survey process and statistical analysis

The survey on groups was conducted based on home addresses. Two main examiners were responsible for the survey in each prefecture-level city. The main examiners were the psychology graduate students with experience in surveying. Before conducting the survey, the researcher conducted special training for the main examiners on conducting the questionnaire survey. The training contents included instructions, contents of the questionnaire, and matters needing attention during the process of conducting the survey. After the survey was completed, the main examiners collected the questionnaires in a unified manner, and sorted out and verified the questionnaires.

In this study, SPSS 19.0 was used for data entry and data analysis. The independent sample T-test was used to analysis the differences of the scores of the variables between people with disabilities and healthy people. Correlation analysis was used to analyze the correlation between various variables. The macro program PROCESS of SPSS was used to test the mediating effect of perceived social support and happiness, and the moderating effect of self-esteem. The number of Bootstrap samples was 5000. Under the 95% confidence interval, gender and age were all controlled as covariates.

Results

Comparative analysis of the scores of the variables

The comparison of the scores of family functioning, perceived social support, happiness, self-esteem, and social avoidance and distress for people with disabilities vis-à-vis healthy people is as shown in Table 1. The results show that scores of people with disabilities are significantly lower than healthy people’s in terms of happiness and self-esteem. Furthermore, it can be seen from the data that all scores of people with disabilities are slightly lower (small effect size) than that of healthy people.

Table 1 Analysis of the scores of the variables for people with disabilities and healthy people
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Correlation analysis among the scores of the dimensions for people with disabilities

The results of correlation analysis in Table 2 show that family functioning, perceived social support, happiness, and self-esteem are significantly negatively correlated with social avoidance and distress; and family functioning is significantly positively correlated with perceived social support and happiness. There is a significant correlation among the variables, which provides a certain precondition for the subsequent mediating effect test. Furthermore, there is no significant correlation between gender and age and other dimensions.

Table 2 Correlation analysis among the scores of the dimensions for people with disabilities
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Analysis of the mediating effects of perceived social support and happiness

From Table 3, it can be found that the indirect effects of perceived social support (95% CI [-0.025, -0.003]) and happiness (95% CI [-0.187, -0.111]) were significant; after the mediating variable entered the equation, the direct effect Bootstrap 95% CI [-0.075, -0.023] did not contain 0, which indicated that perceived social support and happiness had a partial mediating effect between family functioning and social avoidance and distress. Therefore, hypothesis 1 and 2 are supported. See Fig. 2.

Table 3 Summaries of process mediating effect test
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Fig. 2
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The mediation model

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Analysis of the moderating effect of self-esteem

From Table 4, it can be found that the moderated mediation Bootstrap 95% CI [-0.016, -0.003] did not contain 0, which indicated that self-esteem have a moderating effect on the relationship between perceived social support and social avoidance and distress. Therefore, hypothesis 3 is supported.

Table 4 Summaries of process moderating effect test
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In order to further analyze the trend of the moderating effect of self-esteem, self-esteem was grouped based on the mean and plus/minus one SD from mean. See Table 5. Table 5 showed “how” the influence of perceived social support on social avoidance and distress is moderated by self-esteem. The effect measures the influence of perceived social support on social avoidance and distress. The effect shows that when self-esteem is weak, the effect of perceived social support on social avoidance and distress is not significant (effect < 0.01, 95% CI [-0.015, 0.020]). When self-esteem is strong, the effect of perceived social support on social avoidance and distress is significant (effect = -0.02, 95% CI [-0.040, -0.009]).

Table 5 Conditional indirect effect of perceived social support
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Discussion

Influenced by China’s traditional culture, family plays an important role in the physical and mental development of individuals. In particular, for people with disabilities, due to the limitation of their scope of activities and the imperfection of the current social welfare system in China, their living needs are mainly met by family members, family is of even greater significance to their healthy development. Moreover, as people pay more attention to the core value “fairness and justice”, researchers have gradually shifted their focus to vulnerable groups, and the studies on their family functioning are also constantly improving. Social interaction is an important way for individuals to develop physically and mentally. This study has found that family functioning has a reverse predictive power on social avoidance and distress among people with disabilities. In other words, the stronger family functioning is, the lower the level of their social avoidance and distress is, which is consistent with the conclusions of previous studies (Wang et al., 2013). On the basis of constructive repetition of previous studies, this study has constructed and tested a moderated mediation model, and explored the mechanism of impact of family functioning on social avoidance and distress. The above results are of great significance for understanding the role of family functioning of people with disabilities and taking targeted interventions for reducing their social avoidance and distress.

Comparison of the psychological characteristics of people with disabilities vis-à-vis healthy people

This study has found that scores of people with disabilities are all lower than healthy people’s, but the effect size is very small. On the one hand, “fairness and justice” is China’s core value. In recent years, the society has been emphasizing “sharing the fruits of development”; people have paid more and more attention to vulnerable groups, and relevant policies have encouraged people with disabilities to go out of their homes and integrate into society. On the other hand, currently China is still in the transition period, and the pressure exerted by society on people is increasing day by day, which may make people not spend too much time and energy in social activities under heavy pressure (Li et al., 2023), thus indirectly affecting their psychological state.

The mediating effect of perceived social support

This study has introduced “perceived social support”, and explored the specific mechanisms by which family functioning affects social avoidance and distress among people with disabilities. The results reveal that perceived social support is significantly negatively correlated with social avoidance and distress. In other words, the higher the level of perceived social support of people with disabilities is, the more capable they can lower level of their social avoidance and distress, which is consistent with previous research results (Wood et al., 2008). In addition, this study has found that perceived social support has a mediating effect in the process that family functioning reduces social avoidance and distress. This study has also found that family functioning promotes perceived social support of people with disabilities, which is consistent with previous research results (Lei & Kantor, 2012). First of all, family functioning is people with disabilities’ subjective perception of the role of the family in their own self-development and physical and mental growth. It is reflected in solving life problems, communicating with family members, and influencing each other’s emotions. Stronger family functioning enables people with disabilities to experience more warmth of the family, and accordingly improve their ability to perceive support from within or outside the home, that is, the improvement of perceive social support. Secondly, perceived social support is the support from the social members within and outside the home that people with disabilities perceive subjectively, so it is not difficult to understand that when the external support meets their own needs, people with disabilities are more willing to contact with the outside world, and the level of their social avoidance and distress would decline accordingly. In other words, on the one hand, family functioning directly affects social avoidance and distress of people with disabilities; on the other hand, it can indirectly affect their social avoidance and distress by impacting the level of their perceived social support.

The mediating effect of happiness

While introducing “perceived social support”, this study has also introduced “happiness” for exploring the specific mechanisms by which family functioning affects social avoidance and distress among people with disabilities. The results show that the happier people with disabilities are, the higher the level of their mental health is, and their social avoidance and distress can be effectively reduced, which is consistent with previous findings (Verma et al., 2019). Furthermore, this study has found that happiness acts as a “black box” in the relationship between family functioning and social avoidance and distress, that is, happiness has a mediating effect in the process that family functioning reduces social avoidance and distress among people with disabilities. This study has also found that family functioning promotes happiness of people with disabilities, which is consistent with previous research results (North et al., 2008). First of all, as Skinner proposed, the most basic function of a family is to provide certain environmental conditions for the healthy development of family members in physical, psychological, social and other aspects. When the family of people with disabilities gives full play to its due functions, their happiness would continuously rise; conversely, if the family has a negative impact on the individual, it would inevitably hinder the physical and mental development of the individual, and such hindrance would be long-term and gradually affect the individual’s own happiness. In addition, conceptually speaking, the more happy people with disabilities feel in life, the less psychological disorders they have, and the more willing they are to go out of their home and get in touch with the society. Accordingly, the level of their social avoidance and distress would be reduced.

The discovery of such mediating effects has theoretical and practical significance. First of all, it reminds us that the impact of family functioning on social avoidance and distress is complex. Family functioning not only directly affects social avoidance and distress of people with disabilities, but also indirectly affects them through other channels. Secondly, the discovery of such mediating effects provides a basis for reducing social avoidance and distress of people with disabilities and promoting their participation in social life.

The moderating effect of self-esteem

This study has examined whether the mediating effect of perceived social support varies depending on the level of self-esteem. On the basis of the mediating process that family functioning affects social avoidance and distress through, this study has proposed the qualifications“when” the mediating effect is stronger or weaker, and discussed the mediation model in greater depth. Huang Xiting argues that self-esteem is the core part of self-concept in an individual’s personality structure, and the individual’s evaluation degree of himself/herself and his/her experience of sense of value and importance (Huang, 2004). Self-esteem represents an individual’s subjective perception of his/her own value in daily life, which can have an important impact on his/her daily life (Li & Liu, 2016). In this study, we have found that self-esteem is an important “lubricant” in the relationship between perceived social support and social avoidance and distress. With the improvement of the level of people with disabilities’ self-esteem, their social avoidance and distress are more impacted by perceived social support. As previously mentioned, people with disabilities with a high level of self-esteem are more likely to believe themselves as valuable and, accordingly, they are more willing to get in touch with the society; conversely, the individuals with a low level of self-esteem cannot get a good experiences of help and support from interpersonal relationships, thus showing more rejection and avoidance towards interpersonal relationships (Orth et al., 2008). When the people with disabilities have a high level of self-esteem, their perceived social support has a significant inhibiting effect on their social avoidance and distress; while when the people with disabilities have a low level of self-esteem, the impact of their perceived social support on their social avoidance and distress is not significant, that is, at this time, regardless of the level of their perceived social support, the level of their social avoidance and distress would be high. Specifically, with the improvement of the level of their perceived social support, the social avoidance and distress of the individuals with a higher level of self-esteem would decline more rapidly. The schematic diagram of the moderating effect of this study also provides support for the above research results. In other words, a high level of self-esteem enhances the inhibiting effect of perceived social support on social avoidance and distress. The results of this study suggest that in our daily lives, we should attach importance to protecting people with disabilities’ self-esteem. We should not look upon the group of people with disabilities through a “distorted lens”. The society should spare no effort to encourage people with disabilities to integrate into the society, to give full play to their value in the society, and to enhance their self-esteem, thereby reducing their social avoidance and distress.

In summary, for the purpose of reducing people with disabilities’ social avoidance and distress, on the one hand, we should fully leverage the important role of families in promoting the participation of people with disabilities in social activities, such as providing more assistance and convenience to family members of people with disabilities; on the other hand, we should provide assistance to people with disabilities around us, to raise the level of their perceived social support and happiness; in addition, we should protect their self-esteem, and we should not trample on the dignity of people with disabilities (our “friends”) at will. In this way, the willingness of people with disabilities to participate in social activities can be increased.

Research limitations and prospects

This study provides useful exploration for promoting people with disabilities’ participation in social activities, but there are still some limitations.

Firstly, all the test subjects selected for this study are from Henan Province, and the gender distribution of the test subjects is mainly male, so caution should be exercised in inferring results. This study is a cross-sectional study, so there are difficulties in causal inference. If a follow-up study is conducted, the dynamic development of variables would be more appropriately explained. In subsequent studies, the sample selection area can be further expanded, the selection of female subjects can be increased, and follow-up studies can be adopted.

Secondly, the age range of the participants is quite wide. Family functioning differs considerably across this age range, because it encompasses different stages of the life cycle of a family. In subsequent studies, the age grouping should be more detailed, to examine the possible impact of age on people with disabilities.

Furthermore, most existing studies on the psychological and behavioral characteristics of people with disabilities are still superficial, and the studies on the psychological mechanism that affects people with disabilities’ social avoidance and distress are still relatively weak. This study selected 406 people with disabilities for investigation, but did not classify their disability categories and levels of disability. Therefore, follow-up research can focus on examining the differences in psychological characteristics of the individuals with congenital and acquired disabilities, and early and late disability, as well as the individuals with different disability categories and levels of disability.

Finally, in order to better validate research hypotheses, this study only selected the total scores of family functioning, social avoidance and distress, perceived social support, happiness, and self-esteem for analysis, without exploring the subscales. In the future, various subscales can be considered for analysis to examine the potential effects of different dimensions.

Conclusions

Perceived social support and happiness have multiple mediating effects on the relationship between family functioning and social avoidance and distress among people with disabilities;

The mediating effect of perceived social support is moderated by self-esteem, and self-esteem moderates the latter half path of the mediating process of family functioning - perceived social support - social avoidance and distress.

The findings from the study are of theoretical and practical significance for promoting people with disabilities’ participation in social activities and improving the level of their physical and mental health.