Urban Health and Society: Interdisciplinary Approaches to Research and Practice - Part 9 ppt

Notes 61 46. Williams, D. R., and Collins, C. Racial residential segregation: A fundamental cause of racial disparities in health. Public Health Reports, 116 (2001): 404 – 416. 47. Israel, B. A., Schulz, A. J., Parker, E. A., and Becker, A. B. Review of community - based research: Assessing partnership approaches to improve public health. Annual Review of Public Health, 19 (1998): 173 – 202. 48. Barnes, S. L. The Cost of Being Poor: A Comparative Study of Life in Poor Urban Neighborhoods in Gary, Indiana. Albany: State University of New York Press, 2005. 49. Aylott, R., and Mitchell, V. An exploratory study of grocery shopping stressors. British Food Journal, 101 (1999): 683 – 700. 50. Glanz, K., Sallis, J. F., Saelens. B. E., and Frank, L. D. Nutrition environment measures survey in stores (NEMS - S): Development and evaluation. American Journal of Preventive Medicine, 32 (2007): 282 – 289. 51. Glanz, K., and Yaroch, A. L. Strategies for increasing fruit and vegetable intake in grocery stores and communities: Policy, pricing, and environmental change. Preventive Medicine, 39, Suppl 2 (2004): S75 – 80. 52. Cummins, S., Petticrew, M., Higgins, C., Findlay, A., and Sparks L. Large scale food retailing as an intervention for diet and health: Quasi - experimental evalua- tion of a natural experiment. Journal of Epidemiology and Community Health, 59 (2005): 1035 – 1040. 53. Wrigley, N., Warm, D., and Margetts, B. Deprivation, diet and food retail access: Findings from the Leeds “ food deserts ” study. Environment and Planning A, 35 (2003): 151 – 188. c03.indd 61c03.indd 61 6/3/09 11:59:03 AM6/3/09 11:59:03 AM c03.indd 62c03.indd 62 6/3/09 11:59:03 AM6/3/09 11:59:03 AM CHAPTER 4 AN ECOLOGICAL MODEL OF URBAN CHILD HEALTH KIM T. FERGUSON, PILYOUNG KIM, JAMES R. DUNN, GARY W. EVANS LEARNING OBJECTIVES ■ D e fi ne the term ecological model and explain its utility in interdisciplinary research in urban health. ■ Describe key infl uences on the health of urban children at various levels of social organization (e.g., individual, family, community, policy). ■ Describe some of the ways that researchers have studied these infl uences on child health across multiple levels. ■ Identify questions on the health of urban children that require ecological research approaches to answer. c04.indd 63c04.indd 63 6/3/09 11:59:54 AM6/3/09 11:59:54 AM 64 An Ecological Model of Urban Child Health INTRODUCTION Approximately 10 million children under the age of fi ve, including 4 million infants under the age of one month, die every year from causes that are largely preventable, 1 – 3 including preventable and/or treatable diseases such as diarrheal dehydration, acute respiratory infection, measles, malaria, and HIV. 1 , 2 In fact, three of the fi ve most signifi cant contributors to the global burden of disease are primarily or exclusively childhood diseases — namely, perinatal conditions, lower respiratory infections, and diarrheal diseases. 1 , 2 In addition, malnutrition contributes to over a third of all child deaths worldwide. 2 , 4 Although children living in rural areas are almost twice as likely to be malnourished as children living in urban areas, 2 and child mortality rates are typically higher in rural areas, 1 high morbidity, mortality, and malnutrition rates are nevertheless serious concerns for urban children worldwide, especially in the developing world. Furthermore, there is some evidence that, with increasing rates of rural - urban migration and the resulting growth of the urban poor, this urban advantage is decreasing and may not exist when socioeconomic status is controlled for. 5 – 7 Urbanization has been on the incline since the Industrial Revolution, with 46 percent of the world ’ s population living in cities in 2000 as opposed to just 5 p ercent at the beginning of the nineteenth century. 8 , 9 This trend is expected to continue, and in fact, global population growth in the next thirty years will be primarily in cities, with approx- imately two - thirds of the world ’ s population living in cities by 2040. 9 , 10 Children may be disproportionately affected by the environmental challenges inherent in poor urban neighborhoods. 1 1 – 13 Child illnesses and malnutrition infl uence various aspects of child development, including cognitive development and intellec- tual performance. 14 – 24 Further, child mental and physical health predict later health during adolescence and adulthood. 22 , 23 Thus, healthy children grow up to be healthy adults. 22 It is therefore critical that public health researchers and practitioners consider the specifi c factors affecting the health of urban children in developing intervention strategies for improving global health and development. In this chapter, we suggest a conceptual framework wherein the complex interrelations among biological, psycho- social, and physical factors infl uencing child health in urban environments can be studied. AN ECOLOGICAL MODEL Ecological contexts have long been recognized as infl uential in determining popula- tion health. For example, in a discussion on housing conditions and health, Saegert and Evans 25 described the powerful infl uence of housing location and its determinants in shaping the multiple social and physical risks low - income and minority urban fami- lies face. Although some research on urban public health has adopted an ecological per- spective, individual studies tend to assess the infl uences of very specifi c ecological contexts at only one level (e.g., housing and health, neighborhood poverty and crime). c04.indd 64c04.indd 64 6/3/09 11:59:54 AM6/3/09 11:59:54 AM Bronfenbrenner’s Bioecological Model 65 By contrast, in its World Health Report for 2005, the World Health Organization suggests taking an integrated rather than an isolated approach in developing both assessments of and interventions to improve child health. 26 Indeed, considerable research indicates that health interventions are most effective when implemented at multiple levels. 27 – 33 Thus, this chapter calls for an integrated ecological approach to the study of urban public health, employing Bronfenbrenner ’ s bioecological model to assess the infl uences of the ecological context at multiple levels over time on child health. We use this theoretical framework as a heuristic to examine what is known and what needs to be looked at further among the multiple, intersecting ecological niches cities provide for children and their families, with a specifi c focus on how such com- plex urban contexts infl uence children ’ s health. We then lay out an agenda for future work in light of the Bronfenbrenner bioecological model. BRONFENBRENNER ’ S BIOECOLOGICAL MODEL Bronfenbrenner originally conceptualized his bioecological model as a framework for studying development within the actual environments in which people live. 34 – 40 There- fore, this framework lends itself well to the study of urban health within an ecological framework, which necessarily emphasizes the interaction between characte ristics of the person and characteristics of the environment in determining specifi c health outcomes. 29 Further, in contrast to other ecological models employed in urban health research, in the formulation of their bioecological framework, Bronfenbrenner and colleagues have spe- cifi cally identifi ed some of the characteristics of the person and the environment that have an impact on development. They have further specifi ed mechanisms through which interactions between person and environment characteristics may infl uence develop- ment and health. Process - Person - Context - Time Within Bronfenbrenner ’ s bioecological model are four interacting dimensions that should be considered when studying development in context — namely, process, person, context, and time (PPCT; see Figure 4.1 ). 40 The fi rst of these, process, is at the core of the model, and it encompasses exchanges of energy between an organism and the envi- ronment that operate over time. 37 , 39 , 40 These enduring forms of progressively more complex reciprocal interactions between active and evolving human organisms and the persons, objects, and symbols in their immediate external environments, termed proxi- mal processes, are critically important in driving development. 39 , 40 For the purposes of this chapter, proximal processes can be thought of as two - way interactions between the child and the objects and people in his or her immediate environment that may infl u- ence health (see Figure 4.1 ). A simple example would be the ways a child learns to communicate to her parent whether she is ill and needs medical treatment, while at the same time the parent learns to identify the child ’ s need for medical treatment from her behavior. c04.indd 65c04.indd 65 6/3/09 11:59:54 AM6/3/09 11:59:54 AM Process Time (Chronosystem) Person Person Macrosystem Exosystem Microsystem Proximal Processes FuturePresentPast Mesosystem Context FIGURE 4.1 Bronfenbrenner’s Bioecological Model: Process, Person, Context, Time (PPCT) c04.indd 66c04.indd 66 6/3/09 11:59:54 AM6/3/09 11:59:54 AM Bronfenbrenner’s Bioecological Model 67 The power of proximal processes in directing development is posited to vary as a function of various characteristics of the developing person, including behavioral dis- positions, resources, and demand characteristics. 40 The distinction between these different types of person characteristics as conceptualized in Bronfenbrenner ’ s model is not essential for our present purposes. What is important to note is that much research evidence indicates that various characteristics of the developing person do indeed shape both mental and physical health. For example, self - motivation, self - effi cacy, and self - esteem all positively infl uence health and well - being. 41 , 42 Some evidence suggests that the aggressiveness of physicians ’ treatments for persons suffering from heart attacks varies by gender, whereby physicians treat males more aggressively than females. 43 Another defi ning property of Bronfenbrenner ’ s bioecological model is time, which is characterized at three different levels — namely, microtime (continuity vs. discontinu- ity within episodes of proximal processes), mesotime (the periodicity of these episodes of proximal processes across longer time intervals such as days or weeks), and macrotime (changing expectations and events in the larger society that may infl uence individual development). 40 As with the specifi c aspects of the person as conceptualized in the Bronfenbrenner model, the different levels of time are not a critical consideration for our present purposes. However, given the importance of enduring reciprocal interac- tions between persons and their environment in directing development, we can see that the regularity and predictability of events across time directly infl uences children ’ s development, including their health. For example, children living in families with greater turmoil (e.g., frequent arguments between parents and parental divorce or sepa- ration) have elevated cardiovascular activity. 44 , 45 Further, the regularity of events and levels of unpredictability and confusion in the home are related to children ’ s mental health, independent of socioeconomic status (SES). 46 – 48 Finally, in terms of the ecological context, Bronfenbrenner and colleagues have argued that development occurs within four nested and interacting systems — namely the microsystem, the mesosystem, the exosystem, and the macrosystem (see Figure 4.2 ). 40 All four systems are important for understanding children ’ s health in urban environ- ments. The microsystem consists of the settings directly experienced by the child (e.g., the family, the peer group, the school, and the immediate neighborhood). The meso- system consists of connections between these microsystems (e.g., the interaction between parents ’ expectations of the child in terms of nonrisky health behavior and the expectations of the child ’ s peers). The exosystem is comprised of linkages and pro- cesses between settings that do not contain but directly infl uence the child (e.g., parental work settings, the larger neighborhood). The macrosystem is the overarching pattern of micro - , meso - , and exosystems that is characteristic of a given culture or subculture. Thus, the ecological context infl uences the critical proximal processes that underlie human development at multiple levels. In the present chapter, we focus on how both physical and social environmental factors at these different levels infl uence child health. c04.indd 67c04.indd 67 6/3/09 11:59:55 AM6/3/09 11:59:55 AM 68 An Ecological Model of Urban Child Health INFLUENCES ON CHILDREN ’ S HEALTH IN THE URBAN CONTEXT We turn now to a brief discussion of some of the key factors having an impact on urban children ’ s health. It should be emphasized that our purpose here is not to provide a comprehensive overview of the current literature on urban children ’ s health but instead to consider some ways this literature could be understood, and future research could be conducted, within an ecological framework. Thus, we have identifi ed key factors of the physical and social environment that have demonstrated impacts on children ’ s health at each level of the child ’ s environment, from her immediate surroundings to the larger culture in which she is embedded. Some of these factors have been identifi ed by public health researchers as “ leverage points ” — individual and environmental fac- tors that have the most signifi cant impact on a given health outcome. 29 , 31 Understanding the impact of such critical factors on child health is an essential fi rst step in developing appropriate intervention strategies at multiple levels. Macrosystem Physical and Social Environment: Urban Environments The macrosystem is the overarching pattern of micro - , meso - , and exosystem factors characteristic of a given culture or subculture. 40 Urban environments can be seen as a macrosystem that leads to FIGURE 4.2 Bronfenbrenner’s Bioecological Model: Context Macrosystem Attitudes and ideologies of the culture Extended family Friends of family Parents‘ work Child Housing Peers Health services School Neighbors Mass media Social welfare services Family Play- ground Exosystem Mesosystem Microsystem c04.indd 68c04.indd 68 6/3/09 11:59:55 AM6/3/09 11:59:55 AM Infl uences on Children’s Health in the Urban Context 69 specifi c micro - , meso - , and exosystem characteristics, as well as to certain proximal processes acting over time. For example, three hallmark characteristics of urban envi- ronments — namely, complexity, diversity, and density — were introduced in the introductory chapter of this volume. These characteristics operate at multiple levels of the urban environment (including at the immediate level of the family and at the more external level of parents ’ work environments) and infl uence practices and beliefs of parents and their children, thus affecting child health in a unique way (Figure 4.3 ). These characteristics are briefl y considered here in light of their possible role in the health of urban children. We also discuss how these factors fi t within Bronfenbrenner ’ s ecological model. C omplexity is one of the defi ning characteristics of an urban environment. 49 T w o dimensions of complexity in cities are the heterogeneity of urban populations (micro- system) and neighborhoods (microsystem and exosystem), 33 , 49 – 51 both encompassed within the overall characteristic of diversity, and the heterogeneity of both housing (microsystem) and neighborhood (exosystem) density. 52 This heterogeneity is partly a result of the high immigration rates that are typical of cities. Further, cities change over time, a characteristic important to consider in assessing the most critical factors infl u- encing urban child health, which may well change as cities evolve. 49 Some of this high rate of change over time is partly due to the high mobility and residential turnover that Macrosystem Complexity Parents‘ work environments Parents Child Diversity Density Immediate neighborhood Greater neighborhood Environmental chaos Exosystem Mesosystem Microsystem FIGURE 4.3 The Urban Environment as a Macrosystem c04.indd 69c04.indd 69 6/3/09 11:59:55 AM6/3/09 11:59:55 AM 70 An Ecological Model of Urban Child Health are typical of urban environments, which result in disruptions in the child ’ s immediate environment (microsystem) as well as in environments not immediately affecting the child, such as parents ’ work environments (exosystem). These dimensions of complexity render urban environments particularly challenging to study in terms of identifying the various factors infl uencing health. The development and application of multilevel, multidimensional models in studying urban health is thus of critical importance. 27 – 33 , 49 Diversity exists both between and within cities. Between different cities in differ- ent parts of the world, different characteristics of the physical and social environment may be more or less salient and may infl uence health in different ways. 49 For example, the lack of safe water and poor sanitation critically infl uence urban child health in the developing world, 11 , 13 factors that may be less critically important infl uences in the developed world. These can be conceptualized as factors operating at the level of the macrosystem, as they differ between large, complex environments. By contrast, overcrowding and other factors characteristic of poor quality housing in urban areas have a direct impact on child mental and physical health in both developing and developed cities. 11 , 25 , 46 , 50 , 53 , 54 They can thus be considered components of the child ’ s microsystem. These differences require researchers to be cautious in making genera- lizations about the critical infl uences of urban living on health in urban environments. It is also essential that differences between different children ’ s experiences be consid- ered at the level at which they operate. Within cities, diversity encompasses the heterogeneity of both urban populations and neighborhoods and housing quality and type. 33 , 49 – 51 Urban populations are hetero- geneous along the dimensions of ethnicity, income, and socioprofessional status, among other factors. 33 , 49 As we will discuss in some detail later, characteristics such as SES critically infl uence child health and operate both in the microsystem (e.g., within fami- lies, schools, and immediate neighborhoods) and the exosystem (e.g., the larger neighborhood). 55 – 56 Differing neighborhood characteristics are similarly correlated with differential child mental and physical health outcomes, again as detailed later in this chapter. 11 , 46 , 50 , 51 , 53 , 54 Yet another level of complication in assessing the infl uences of various ecological factors on child health in urban environments is the fact that person and neighborhood characteristics are often interrelated; for example, neighborhood segregation tends to occur along ethnic and socioeconomic lines. 25 , 50 We thus discuss SES as operating across levels in the following section. Further, both housing and neighborhood density are heterogeneous within cities such that low - income, minority families are more likely to live in homes and neighborhoods characterized by residential crowding. 52 Thus, poor, ethnic minority urban children are exposed to considerably more environ- mental and psychosocial stressors related to poverty than are suburban white children; these stressors in turn infl uence child health at multiple levels. 15 , 52 , 55 , 56 In many urban areas, inequality is pervasive; low - income residents, including children, lack access to adequate health and social services, which typically operate at c04.indd 70c04.indd 70 6/3/09 11:59:55 AM6/3/09 11:59:55 AM . J., Parker, E. A., and Becker, A. B. Review of community - based research: Assessing partnership approaches to improve public health. Annual Review of Public Health, 19 ( 199 8): 173 – 202. . welfare services Family Play- ground Exosystem Mesosystem Microsystem c04.indd 68c04.indd 68 6/3/ 09 11: 59: 55 AM6/3/ 09 11: 59: 55 AM Infl uences on Children’s Health in the Urban Context 69 specifi c micro - , meso - , and. social and physical risks low - income and minority urban fami- lies face. Although some research on urban public health has adopted an ecological per- spective, individual studies tend to assess