4. The need for longitudinal research on mental health
According to Life Course Theory, early life experiences or states significantly influence later outcomes. Mental health is an accumulative process, and has the potential to alter subsequent life-course.
Furthermore, the mental health of individuals during their the life-course is not static, but rather a dynamic developmental process influenced by individual life experience. The trajectory of individual mental health cannot be understood unless it is possible to investigate “time” and “changes over time”.
Cross-sectional studies provided valuable information regarding certain issues. However, longitudinal research is required to understand certain phenomena that change over time (namely mental state), and particularly how and why they change.
According to Menard (2002), longitudinal research is defined in terms of both data and method of analysis, and the criteria used in its definition are as follows: (a) data are collected for each item or
variable over two or more different time periods; (b) the subjects analyzed are the same or at least comparable between or among periods; and (c) the analysis involves comparison of data between or among periods. The current study uses the same variables and subjects from four waves of data of the Taiwan Education Panel Survey (TEPS), thus meeting criteria (a) and (b); moreover, Hierarchical Linear Regression (HLM) can measure changes over time and enable the comparison of different time period, meeting criterion (c). Therefore, this study can be considered a longitudinal study, and thus is well suited to describe the trajectory of mental health.
Parental Divorce and Parental Marital Conflict 1.The Effects of Parental Divorce
Adolescence is a unique life stage during which individuals experience major physiological and psychological changes. The mental health of adolescents strongly influences adult outcomes (Amato, et al., 1995; Glenn & Kramer, 1985; Pallas, 2003), and family is the most important determinant of mental
health in young people (Johansson, et al., 2007).
Parental divorce during childhood had both short- and long-term negative impacts on offspring mental health, including anxiety and psychological distress (Amato, 1988; Paul R. Amato & A. Booth, 1991; Ä ngarne-Lindberg & Wadsby, 2009; Chase-Lansdale, et al., 1995; Maier & Lachman, 2000;
McLanahan & Bumpass, 1988; McLanahan & Sandefur, 1994). Individuals who experienced parental divorce were more likely than those who grew up in two-biological-parent families to have poorer mental health.
Childhood parental divorce was associated with adult psychological state, including] overall happiness (Amato, et al., 1995; Glenn & Kramer, 1985) and depressive symptoms (McLeod, 1991).
Cherlin, Chase-Lansdale, and McRae (1998) also suggested that parental divorce during childhood had a long-term effect.
Videon (2002) used longitudinal data to investigate the short-term effects of parental divorce, and found that adolescents with divorced parents are more likely to be depressed within two years of the divorce than are their peers from two-biological-parent families. Chase-Lansdale, Cherlin & Kiernan (1995) suggested that parental divorce had moderate long-term effects on young adults. Young adults who experience parental divorce during childhood have higher total Malaise Inventory scores. A recent Swedish study showed that during the 15 years following divorce, divorced women are more likely than non-divorced women to have lower mental health, including higher depression or anxiety
(Ä ngarne-Lindberg & Wadsby, 2009).
Maier and Lachman (2000) examined the influences of early parental experiences on
middle-aged adults, and suggested that middle-aged men and women from families that have undergone parental divorce exhibit higher prevalence of physical health problems, and men show higher rates of depression. Using samples from Taipei City, Cheng (2001) analyzed the life adjustment of fifth to eighth graders from two-biological-parent and single-parent families, and found the latter group to be
disadvantaged in certain dimensions of social adjustment, including social adjustment. She also noted that the causes of the disadvantaged situation in single-parent families involve more than just the absence of one parent, but rather involve a combination of numerous complex factors.
2.The Effects of Parental Marital Conflict
Studies suggest that that both parental divorce and parental marital conflict, negatively influence outcomes in children. Children and adolescents who experience harmful parental conflict are more likely to [have OR suffer] both internalizing and externalizing problems(Buehler et al., 1997; Lindsey, Chambers, Frabutt, & Mackinnon-Lewis, 2009; Schoppe-Sullivan, Schermerhorn, & Cummings, 2007;
Wang & Chen, 2010), and exhibit poor academic performance (Mechanic & Hansell, 1989).
Lindsey et al. (2009) used longitudinal data to analyze the effect of marital conflict on
adjustment of children, including internalizing and externalizing symptoms. The children in their study ranged from 8 to 16 years old, and the analytical results indicate that after controlling for parenting process and early adjustment of children, marital conflict still negatively impacts later internalizing symptoms, but not externalizing symptoms. Schoppe-Sullivan et al. (2007) also used longitudinal data and included 268 mother-adolescent (fifth grade) dyads in their study analyzing the influences of marital conflict on overt and relational aggression in adolescents. The results demonstrate that marital conflict both directly and indirectly influences adolescent aggression.
Mechanic and Hansell (1989) also used longitudinal data to analyze the influence of marital conflict on adolescent well-being, including depressed mood, anxiety, self-esteem, and physical symptoms. Their results suggested that higher family conflict increased depressed mood, anxiety, and physical symptoms in adolescents.
Amato et al. (1995) provided several potential mechanisms for the negative impact of marital conflict on children. First, conflict between parents is a direct stressor, and parental arguments can cause children to experience fear, anger, or aggression. Conflict between parents or between parents and children can cause physical violence and increase the risk of psychological and behavioral problems, and can also reduce child academic performance. The egocentricity of young children makes them likely to blame themselves for parental conflict, resulting in lower levels of psychological well-being.
Moreover, children learn some of their social skills from the behavior of their parents, and so parents adopting conflict behaviors rather than communication or compromise, may lead to children learning inappropriate social skills.
3.The Effects of Pre-divorced Parental Marital Conflict
Despite the above literature addressing the influences of parental divorce or marital conflict on offspring, researchers increasingly consider “divorce” a continuous process rather than a single event,
and consequently consider it in the context of parental marital conflict. Studies suggest that martial conflict can contribute partly, but not completely, to subsequent offspring outcomes (Amato, et al., 1995;
Booth & Amato, 2001b; Hanson, 1999). Hanson (1999) suggested that children exposed to high levels of pre-divorce marital conflict are neither better nor worse off following parental divorce, but parental divorce can seriously and negatively influence children exposed to low levels of pre-divorce marital conflict. Amato, Loomis and Booth (1995) and Booth and Amato (2001b) obtained similar findings, namely that parental divorce reduces the well-being of offspring in families with low levels of pre-divorce marital conflict, and increases the well-being of offspring in families with high levels of pre-divorce marital conflict. Cherlin (1998) also indicated that some of the negative influences of parental divorce on offspring during childhood or adolescence appeared before parental divorce, and the influences lasted into adulthood.
It is important to distinguish pre-divorced martial conflict from general parental marital conflict is because for two-parent families, the negative influence of parental marital conflict on offspring is well-documented. However, for divorced single-parent families, the role of pre-divorced marital conflict is not clear yet. Amato et al. (1995), Booth and Amato (2001) and Hanson (1999) all suggested that parental divorce decreases offspring well-being of low levels of pre-divorced parental marital conflict families, and the prior two studies suggested that parental divorce increase offspring well-being of high levels of pre-divorced parental marital conflict families, but the Hanson’s (1999) study suggested that parental divorce neither increases or decreases offspring well-being of high levels of pre-divorced parental marital conflict families.
Wheaton (1990) pointed out that life transition events (i.e. job loss, divorce, retirement etc.) is a stressor for individuals. However, when the prior chronic stress (before the events occur) exists, and more stress can be relief from the existing stress, and then the life transition event is actually beneficial for individual mental health. On the other hand, when the life transition event relieves less existing stress
than the new stress it brings, and then the life transition event is harmful for individual mental health. His argument can be expressed in Figure 1.
Figure 1. Wheaton’s concept of how life transition event affect mental health
The key factor of how life transition event, in this study is parental divorce, can affect individual mental health is depending on the context of the life transition event occurs, and the pre-divorced parental marital quality is one dimension of the context. However, the literatures of pre-divorced marital conflict on offspring mental health is relatively few when comparing with the literatures of marital conflict, and more studies need to be done to understand the context of parental divorce occurs. This study tends to broaden the existing literature of the influences of parental divorce and martial conflict, but also to explore the effects of pre-divorced marital conflict on offspring mental health in Taiwanese context.
Parental Involvement
Research has shown that positive parent-child relations, such as parental caring, acceptance, open parent-child communication, and generally supportive parent-child relations, are correlated with
Increasing mental health existing stress Life
transition event
Decreasing mental health
positive adolescent outcomes, including better mental health (Astone & McLanahan, 1991; Crouter, MacDermid, McHale, & Perry-Jenkins, 1990), lower internalizing, externalizing, and substance use problems, and higher psychosocial competence (Steinberg, 2001). Moreover, Flouri (2004) found that parental involvement with offspring at seven years old can predict psychological functioning feeling (namely unhappy, depressed, or under strain), psychological distress (namely feeling miserable and depressed, getting easily annoyed by others, and suffering a nervous breakdown), and life satisfaction (namely how life has turned out so far, and expectations for the next ten years) of offspring at 42 years old.
Furthermore, parental involvement is also a protective factor for children's adjustment after parental divorce. After reviewing twenty-four studies, Leon’s (2003) suggested that parental warmth and responsiveness are important protective factors throughout childhood and adolescence, but parental monitoring and involvement becomes more important in middle childhood and adolescence because children spend more time in school and with peers. Therefore in this study, parental involvement serves as the protective factors to reduce the negative influence of parental divorce and marital conflict on adolescent mental health.
Parental Education and Household Income
Studies have suggested that children or adolescents with higher household income and parental education particularly paternal education are less likely to exhibit emotional or behavioral problems (Bradley & Corwyn, 2002; Carlson & Corcoran, 2001; Morris, 2003). On the other hand, other studies have suggested that students with higher household income and parental education have worse mental health (Luthar & D'Avanzo, 1999). In Western countries, controversy continues regarding the effect of parental education and household income on offspring mental health state. Yang (2005) analyzed the mental health of students in Taiwan, and found that after controlling for educational achievement, neither
parental education nor household income exerted a significant effect.
Gender Differences
Mental health state differs between males and females. Studies have suggested that females are more likely than males to recognize emotional problems (Fletcher, 2008; Yokopenic, et al., 1983), frequently report mental health difficulties, or internalize mental health difficulties (Andersson et al., 2010). According to the National Adolescent Health Information Center (2006), young females are more likely to exhibit sad feelings, suicidal ideation and attempts, while young males are more likely to actually commit suicide
Moreover, Tick, Ende and Verhulst (2008) used samples of Dutch adolescents to analyze trends in emotional and behavioral problems between 1993 to 2003. Their results suggested that thought problems, internalization problems, somatic complaints, suicidal ideation and self-harm were more likely to increase among girls than boys during the ten year study period.
School Program Type, School Type, and School Urbanization
In the East Asian region, the competitive educational system is an unique social background (Yi, Wu, Chang, & Chang, 2009). Educational achievement is highly valued by society, teachers, and parents highly value. Adolescents is expected to study hard and enter good high school and college (Hsu, 1971).
Therefore, the pressure of having good educational achievement is high and might decrease adolescent mental health. However, due to the educational tracking system of high school in Taiwan, adolescents who can choose either academic-oriented or vocational-oriented programs or high schools, and the pressure of educational achievement might be decreased for adolescent who choose vocational-oriented programs or schools, because they are not expected to have high academic achievement anymore, but rather to have more practical skills or abilities. Moreover, school type (such as public or private) and
school urbanization (such as rural, sub-urban, and urban) are both correlated with the educational tracking system. In general, school with higher educational pressure tends to be academic-oriented, public, and normally located in urban areas. Therefore these factors need to be controlled for.
Using Hierarchical Linear Modeling in Longitudinal Research 1.Why use Hierarchical Linear Modeling(HLM)?
In the social sciences, data structures are frequently hierarchical (Raudenbush & Bryk, 2002).
This study uses variables to describe individuals, but the individuals are grouped into larger units, each comprising numerous individuals, and other variables describe these higher order units. Individuals within a population exist within clusters. For example, students are grouped into classes, classes are grouped into schools, schools are grouped into areas, and so on. Data are often nested within persons, organizational units, and/or communities (O'Connell & McCoach, 2008; Raudenbush & Bryk, 2002).
Numerous studies neglect this type of data structure. When the traditional linear regression employs nested data, it violates the assumption that observations of any individual are not systematically related to observations of any other individual. HLM is a particular regression technique used to consider hierarchical structures, and thus can model the nested data structure and provide individual level and cross level effects.