Family’s Subjective Economic Status and Children’s Matrix Reasoning: Blacks’ Diminished Returns

Background: Due to a pattern known as Marginalization-related Diminished Returns (MDRs), historically oppressed non-Hispanic Black Americans show weaker effects of economic status on health and development, when compared to socially privileged non-Hispanic White Americans. Such MDRs are also documented for the effects of economic status on the school performance of non-Hispanic Black children. However, the existing knowledge is minimal on similar diminished returns on children’s intelligence. Aim: To compare racial and ethnic groups for the effect of subjective economic status on children’s cognitive performance, we compared non-Hispanic White and non-Hispanic Black children for the effects of subjective economic status on children’s matrix reasoning. Methods: This cross-sectional study included 7898 children from the Adolescent Brain Cognitive Development (ABCD) study. The predictor variable was subjective economic status, which was treated as a continuous measure. The primary outcome was children’s matrix reasoning, a domain of cognitive performance, measured by the Wechsler Intelligence Scales for Children-IV (WISC-V) matrix reasoning total score. Results: Overall, high subjective economic status was associated with higher matrix reasoning score. Race showed a statistically significant interaction with subjective economic status on children’s matrix reasoning score. This interaction suggested that high subjective economic status has a smaller boosting effect on increasing matrix reasoning score for non-Hispanic Black children relative to non-Hispanic White children. Conclusion: The degree by which subjective economic status correlates with matrix www.scholink.org/ojs/index.php/rhs Research in Health Science Vol. 6, No. 1, 2021 2 Published by SCHOLINK INC. reasoning score, an important domain of cognitive performance, depends on race and racialization. Non-Hispanic Black children may show weaker gains in matrix reasoning from their subjective economic status than their non-Hispanic White counterparts. To minimize the racial gap in cognitive performance, we need to address diminished returns that occur as a result of the racialization of racial and ethnic minority children. Not only should we equalize economic status, but also increase the marginal returns of economic status for racial minorities, particularly non-Hispanic Black families. Such efforts require public policies that go beyond access and also consider how we can empower non-Hispanic Black communities and families so they can more effectively leverage and utilize their economic resources to secure measurable and tangible outcomes. Structural and societal barriers such as residential and school segregation may hinder non-Hispanic Black children from receiving the full effects of their family-level economic status on a variety of outcomes, including their cognitive performance.

Although both subjective and objective aspects of economic well-being and economic status matter (Senn, Walsh, & Carey, 2014), most of the existing literature has focused on objective economic indicators such as parental education, household income, parental employment, marital status, and wealth (Marmot, 2004). These indicators, however, only reflect some specific domains of economic well-being. Complementary to these objective measures are subjective indicators of economic well-being that capture how the individual and family perceives the sufficiency of economic means on a day-by-day basis. These subjective indicators have the potential to reflect economic strains and describe how an individual values their social status relative to others (Assari, Boyce, & Bazargan, 2020;Manuck, Phillips, Gianaros, Flory, & Muldoon, 2010;Moon, 1987;Wright & Steptoe, 2005).
Two competing and complementary models have been used to study the simultaneous and joint effects of race and subjective economic status on children's outcomes. The first approach, which has traditionally www.scholink.org/ojs/index.php/rhs and historically dominated the field, attributes racial and ethnic gaps in children's outcomes to the scarcity of economic resources and a high prevalence of risk factors in the lives of racial minority families such as non-Hispanic Blacks (Bell, Sacks, Thomas Tobin, & Thorpe, 2020;Fuentes, Hart-Johnson, & Green, 2007;Kaufman, Cooper, & McGee, 1997;Samuel, Roth, Schwartz, Thorpe, & Glass, 2018). Some of the researchers who follow this line of work have suggested that economic status may partially mitigate the effects of race on children's outcomes (Assari, 2016(Assari, , 2017aAssari, Khoshpouri, & Chalian, 2019). This research advocates for enhancing the economic status of racial and ethnic minority groups as the main strategy to close the racial differences in children's outcomes (David R Williams, 1999;D. R. Williams, Costa, Odunlami, & Mohammed, 2008).
The second model, however, argues that economic resources may have differential effects on generating childhood outcomes across racial groups.  (Assari, 2018e;Assari, 2018f) generate fewer desired outcomes for racial and ethnic minority groups. Non-Hispanic Black children and non-Hispanic White children differ in their opportunities to mobilize their economic resources to secure tangible outcomes (Assari, 2017bAssari, Caldwell, & Mincy, 2018a;Assari, Caldwell, & Zimmerman, 2018;Assari & Hani, 2018). Given the existing MDRs, non-Hispanic Black children develop worse than expected outcomes when compared to non-Hispanic White children, a pattern seen across all economic levels (Assari, 2017b;Assari, Caldwell, & Mincy, 2018a;Assari, C. H. Caldwell, & R. B. Mincy, 2018b;Assari, Thomas, et al., 2018). While these MDRs are shown for elements such as attention, impulsivity, inhibitory control, and reward orientation, we are not aware of any studies on matrix reasoning, which is an important domain of cognitive performance.
Matrix reasoning (Chierchia et al., 2019;Harrison, Shipstead, & Engle, 2015) is a major element of cognitive performance. Matrix reasoning (Allen & Fong, 2008;Harrison et al., 2015;Knight, 2003) is a type of visual-spatial problem solving, and closely correlates with general intelligence (Gottfredson, 1998). Matrix reasoning measurement commonly involves a series of figures in which there is a pattern, with one figure in the series intentionally left blank. The individual is shown an array of possibilities so the person who indicate which figure would complete the series or pattern (Mayes & Calhoun, 2008).
Matrix reasoning correlates with overall cognitive performance and is highly affected in psychiatric conditions such as Attention Deficit Hyperactivity Disorder (ADHD), autism, psychosis, and learning disabilities. Matrix reasoning is commonly measured using the widely IQ measure, Wechsler Intelligence Scales for Children-IV (WISC-IV) (Dombrowski, Canivez, & Watkins, 2018). Matrix reasoning is independent of the speed or motor planning. Such lack of requirements makes matrix reasoning a reliable test that is not confounded by executive function and executive control (Mayes & Calhoun, 2008). Matrix reasoning score also reflects strengths and weaknesses in verbal and visual reasoning, and attention in children with and without mental and intellectual disorders (Mayes & Calhoun, 2008).

Aims
To extend the knowledge that is already available regarding the combined effects of race/ethnicity and subjective economic status on children's cognitive performance, we built a study on the MDRs theory to

Sampling
In the ABCD study, participants were limited to 9-10 years old children who were recruited from multiple cities across several states. In total, 21 ABCD centers were involved in the recruitment of the children. The main strategy to recruit participants to the ABCD study was to utilize the US school system (Garavan et al., 2018). Eligibility criteria for the current analysis were not being a twin, not being Hispanic, and having valid data on race, demographic factors, and cognitive performance. Only non-Hispanic Black or non-Hispanic White individuals could enter our analysis.

Study Variables
The study variables included race/ethnicity ( (independent variable), and children's matrix reasoning (dependent variable).

Demographic and Socioeconomic Confounders
Age, sex, household size, parental education, parental employment, and parental marital status were the confounders. Parents were asked to report the age of their children. Age was a dichotomous variable 1 for 10 and 0 for 9 years old. Sex was also dichotomized as 1 for males and 0 for females. Household size was a continuous measure self-reported by the parent. Parental marital status was equal to 1 for married and equal to 0 for unmarried. Parental education was a continuous measure from 1 to 21. Parental employment was self-reported by the interviewed parent and was coded 1 for the presence of any employed parent in the household and 0 for no employed parent in the household.

Primary Outcome
Matrix reasoning (cognitive performance). The ABCD study used the Wechsler Intelligence Scale for Children -V (WISC-V) to measure the cognitive performance of the children (Raiford et al., 2016).
WISC is one of the most commonly used measures to capture children's IQ and cognitive performance (Baron, 2005). In this analysis, we used the WISC-V matrix reasoning total score data (pea_wiscv_tss) as our outcome (Raiford et al., 2016). This variable is pre-calculated and was already available in the ABCD study. Our measure of WISC-V matrix reasoning had a normal distribution. For this continuous measure, a higher score indicates higher cognitive performance (Covin & Hatch, 1977;Salthouse, 1993;Soulieres et al., 2009).

Independent Variable
Subjective economic status. This study measured subjective economic status using seven items.
Participants were asked "In the past 12 months, has there been a time when you and your immediate family experienced any of the following:" 1) "Needed food but couldn't afford to buy it or couldn't afford to go out to get it?", 2) "Were without telephone service because you could not afford it?" 3) "Didn't pay the full amount of the rent or mortgage because you could not afford it?", 4) "Were evicted from your home for not paying the rent or mortgage?", 5) "Had services turned off by the gas or electric company, or the oil company wouldn't deliver oil because payments were not made?", 6) "Had someone who needed to see a doctor or go to the hospital but didn't go because you could not afford it?" and 7) "Had someone who needed a dentist but couldn't go because you could not afford it?" Responses were 0 or 1. A mean score (a continuous measure) was calculated, with a range varying between 0 and 1, where higher scores were indicative of higher subjective economic status (Assari, Preiser, Lankarani, et al., 2018;Assari, Smith, Mistry, et al.,

Moderator
Race. Race/ethnicity was identified by the parents. Race/ethnicity was a categorical variable and coded 1 for non-Hispanic Black and 0 for non-Hispanic White.

Data Analysis
SPSS 23.0 (IBM, New York, NY, USA) was applied for data analysis. Mean, standard deviation (SD), frequency, and relative frequency (%) were reported to describe the sample. We described our sample overall and by race/ethnicity. We performed a Pearson bivariate test to rule out multicollinearity before performing our linear regression model. For our multivariable models, we applied multiple linear regression models. Our first two models were performed in the overall sample. Our last two models were performed in each race. Model 1 did not have any interaction terms. Model 2, however, did add an interaction term between race/ethnicity and subjective economic status. Model 3 was performed in non-Hispanic White children. Model 4 was performed in non-Hispanic Black children. We reported b, SE, 95% CI, and p value.

Ethical Aspect
This analysis was exempt from a full Institutional Review Board (IRB) review by Charles R. Drew University of Medicine. The mother study (ABCD), however, was approved by the IRB at the University of California, San Diego (UCSD). Assent and consent were received from children and their parents, respectively (Auchter et al., 2018).

Descriptives
As shown in Table 1, 7898, 9-10 years old children were included in our analysis. From this number, most were non-Hispanic Whites (n = 5839; 73.9%) and the rest were non-Hispanic Blacks (n = 2959; 26.1%).  Table 2 presents the bivariate correlation between various study variables in the overall sample.
Subjective economic status was positively correlated with cognitive performance. Other factors that were correlated with the cognitive score were race/ethnicity, sex, parental employment, parental marital status, and parental education.

Pooled Sample Multivariate Analysis
In subjective economic status on matrix reasoning is weaker for non-Hispanic Black children relative to their non-Hispanic White counterparts (Table 3).

Discussion
Overall, high subjective economic status was associated with higher children's matrix reasoning.
However, the boosting effect of subjective economic status on children's matrix reasoning was diminished for non-Hispanic Blacks when compared to non-Hispanic Whites.
The observed diminished returns (MDRs) of economic status on matrix reasoning for non-Hispanic Black children compared to non-Hispanic White children are similar to what the previous research has suggested (Assari, , 2018cAssari, 2019a;. MDRs are repeatedly established by research both within and between individuals and families. These MDRs are robust and reliable as they are found to hold across all economic levels, developmental phases, types of outcomes, and visible and non-visible sources of marginalizing identities (Assari, 2017b;. MDRs are shown for income (Assari, Caldwell, & Mincy, 2018a), education , employment (Assari, 2018d), and marital status (Assari, Caldwell, & Zimmerman, 2018). Economic status results in more gain for non-Hispanic White children than non-Hispanic Black children (Assari, Caldwell, & Mincy, 2018a;Assari, Caldwell, & Mincy, 2018b;Assari, Thomas et al., 2018), adults , and older adults (Assari & Lankarani, 2016). Also, MDRs not only apply to non-Hispanic Blacks (Assari, Thomas et al., 2018), or Hispanic Whites (HWs) (Assari,  LGBTQ individuals (Assari, 2019a). For example, some studies have documented racial differences in family structure effects on health (Cross, 2020). That means, racial differences exist in the effects of parental marital status (an indicator of economic status) on children's health; the return on living in a two-biological-parent family is weaker for Black children than White children (Cross, 2020).
A wide range of societal mechanisms is likely to be involved in causing MDRs of economic status in non-Hispanic Black families. Non-Hispanic Black communities, families, and individuals face a wide range of stressors that are not due to economic resources, but rather social stratification and racism.
These non-economic adversities are environmental, structural, and are related to race, racialization, and marginalization, adversities that are seen across all economic levels (Bowden, Bartkowski, Xu, & Lewis Jr, 2017). The marginal returns of economic mobility may be limited when upward social mobility is more difficult for a specific group (Chetty, Hendren, Kline, & Saez, 2014). Increased exposure to stress is believed to reduce children's ability to gain from their available economic status resources such as parental education and income. It is shown that for non-Hispanic Black families, an increase in economic status means an increase in experience Assari, F. X. Gibbons, & R. Simons, 2018a;Assari, F. X. Gibbons, & R. L. Simons, 2018b;Assari & Moghani Lankarani, 2018) and vulnerability (Assari, Preiser, Lankarani et al., 2018)to discrimination. This might be because non-Hispanic Black families who have economic resources are more likely to be surrounded by non-Hispanic White families, which increases their exposure to discriminatory events (Assari, Gibbons, et al., 2018a;Assari, Gibbons, et al., 2018b). Needless to say, high levels of race-related and general discrimination, which operate as a risk factor for many poor health outcomes such as cognitive decline, reduce the expected gains from economic resources Assari, Preiser, Lankarani et al., 2018).
Residential segregation may be a reason why we observe differences between non-Hispanic Black and non-Hispanic White contextual exposures. It might be a result of residential and school segregation that school options are limited for non-Hispanic Black children, across all economic levels. As a result, Black children are sent to poor schools that are located in highly segregated areas, and this is even true for families that have economic resources (Assari, 2019b;. This results in the differential effects of Socioeconomic Status (SES) on education and schooling of non-Hispanic White children and non-Hispanic Black children. While high SES non-Hispanic White children attend sufficiently resourced schools that are located in suburban areas with available funding and highly prepared teachers, non-Hispanic Black children are sent to schools that have a lower level of resources and less prepared teachers (Jefferson et al., 2011).
In this study, we did not argue that race has a fixed and unmodifiable effect on cognitive performance.
We are not making a statement in the politically and morally charged debate on the effect of race on IQ.
We conceptualize race as a proxy of racialization, and we exclusively focused on the effect of race as a social factor, on bounding the health effects of economic status. The argument here is that in a race aware society that has historically used racism to hold non-Hispanic Blacks behind, family level and individual level factors are not enough to secure desired outcomes. This is in part because non-Hispanic Black families who have high economic resources still report high levels of stress as they face a wide range of societal barriers Assari & Moghani Lankarani, 2018). Non-Hispanic White families with similar economic status are not required to deal with such stressors in their daily lives (Assari & Mohsen Bazargan, 2019b;Assari, Preiser, & Kelly, 2018;Assari, Preiser, Lankarani, et al., 2018).
Although the lack of economic resources imposes one type of risk to non-Hispanic Black communities and families, this is not the only disadvantage that Black families experience in the US. MDRs are reflective of another set of disadvantages in the life of Black families (Assari, 2017b;.
While the solution to a lack of resources is to equalize access to resources, the solution to the second type requires equalization of the returns of economic resources. The MDRs-related inequalities are resistant to closing the racial gap in economic resources. Resolving MDRs requires addressing the structural barriers that are root causes of MDRs-related inequalities, even in families that have high SES.
It is essential to dissolve inequalities that are due to a lack of economic resources from those that are due to their diminishing returns. Researchers and policymakers should be able to recognize the difference between the two classes of adversities and provide and suggest specific solutions to each. Policymakers should also be aware that non-Hispanic Blacks are experiencing double disadvantage and jeopardy, one for low economic resources, and one for lower return of such resources when they become available to them. A real solution should make economic resources available to the communities of color and at the same time ensure that those resources are utilized by individuals and families Assari, 2018h).
To explain causes of MDRs, scholars have studied the daily experiences of middle-class Black families (Chiteji & Hamilton, 2002;Weitzman, Byrd, & Auinger, 1999). Reviewing the work of the above-mentioned research on Black middle class suggests that middle-class non-Hispanic Black families experience their class and social status differently when compared to middle-class non-Hispanic White families (Hudson, Sacks, Irani, & Asher, 2020). It is shown that high subjective economic status may even operate as a source of vulnerability for non-Hispanic Black families, as it both increases exposure Assari, Gibbons, et al., 2018a;Assari, Gibbons, et al., 2018b; and sensitivity (Assari, Preiser, Lankarani, et al., 2018)to discrimination.

Study Limitation
The current study had a few non-fatal limitations. With a cross-sectional design, we do not read our findings as causal associations between SES and children's cognitive performance. We only tested MDRs of subjective economic status, and MDRs of other SES indicators were not investigated. While we controlled for parental education, employment, and marital status, other indicators such as family income, family wealth, and neighborhood economic status may also show differential effects on Black and White children's cognitive performance. This study also did not test contextual variables that cause the associations between economic resources and developmental outcomes to differ across racial groups.

Conclusion
When compared to non-Hispanic White children, non-Hispanic Black children show weaker effects of subjective SES on their matrix reasoning. It is still unknown why high-SES non-Hispanic Black children show worse-than-expected outcomes.

Conflicts of Interest:
The authors declare no conflicts of interest.
Author Funding: SA is supported by the following National Institutes of Health (NIH) grants: CA201415 02, DA035811-05, U54MD007598, U54MD008149, D084526-03, and U54CA229974. This is a multisite, longitudinal study designed to recruit more than 10,000 youth age 9-10 and follow them over 10 years into early adulthood. The ABCD Study is supported by the National Institutes of