GPH exam 4

Comprehensive Exam Notes: Chapters 9, 10, & 11Chapter 9: Ecological and Structural Approaches to Improving Public Health1. The Ecological PerspectiveDefinition: An ecological approach targets multiple influences on health simultaneously rather than focusing only on individual knowledge, willpower, or biology. Systemic Interventions: Involves long-standing, systemic changes to physical, legal, economic, and social environments. Obesity Epidemic Example:Approximately $\frac{2}{3}$ of U.S. adults and $\frac{1}{5}$ of children are obese or overweight, heightening the risk for chronic diseases. Environmental contributors include lack of access to full-service supermarkets/grocery stores, high cost of healthy whole foods, and a lack of safe, accessible places to exercise. Reversing the epidemic requires an ecological solution that acknowledges how environmental conditions dictate individual choices. 2. Risk Environment & Social EtiologyRisk Environment (Link & Phelan, 1995): Environments contribute significantly to behavior because they "set the stage" for individuals to engage in unhealthy or risky practices. Some settings systematically foster far more risk than others. Social Etiology of Disease: The underlying root causes of many health conditions reside within the socio-cultural and physical environment rather than personal or biological flaws. 3. Bronfenbrenner’s Model of Human Development (1979)Examines how human development is shaped through mutual, bidirectional transactions between people and the environmental systems they navigate. Ecological LevelFormal DescriptionConcrete Public Health ExampleMicrosystemThe immediate, face-to-face setting where a person actively lives and operates; a dynamic, reciprocal system where the person affects and is affected by the environment. Immediate family, classroom, small peer group, neighborhood block. MesosystemThe interactions and connections occurring between two or more microsystems. A child’s parents meeting directly with their school teacher; family dynamics affecting an adolescent’s peer group. ExosystemSettings in which the individual has no direct, active involvement, but decisions made there still influence their daily life. A parent’s workplace (overtime policies, wage cuts), local municipal economic status, parents' marriage stability. MacrosystemThe overarching cultural, societal, and subcultural context in which all underlying systems function. Cultural values, federal laws, national economic resources, societal expectations, and customs. 4. Structural Model of Behavior (Cohen et al., 2000)Identifies four distinct environmental pillars that shape behavior: Availability / Accessibility:Physically limiting products or modifying their cost alters consumption. Rule: The greater the access, the more likely the behavior. Examples: Raising cigarette excise taxes limits availability; stocking contraception in neighborhood pharmacies expands accessibility. Physical Structures:The built environment directly impacts health behaviors and unintended injury. Examples: Bike lanes encourage exercise; low, unbarricaded windows cause pediatric fall injuries. Social Structures:Invisible institutional rules, organizational norms, and policies that govern daily behavior (e.g., workplace smoking bans, school attendance policies). Effects of Media:Mass communication (TV, internet, ads, print, videogames) reshapes social norms regarding the acceptability, attractiveness, and normality of health behaviors. 5. Behavioral Ecological Model (BEM) (Hovell et al., 2009)Extending Operant Conditioning: Applies B.F. Skinner’s operant conditioning principles (reinforcement, contingencies, consequences) to the societal and population level. Meta-contingencies: Social reinforcements and consequences delivered by an entire social system. Strength of a Meta-contingency: Defined by the probability of encountering social consequences. (e.g., In an area where public smoking bans are strictly enforced and culturally supported, the probability of facing social penalties is extremely high). 6. Health Disparities & Inequity FrameworksMinority Stress Theory:Proposes that hostile, challenging social environments produce chronic, daily stress for minority groups. Three Tenets:Minority status is linked to distal sources of stress (external, objective events: discrimination, violence, systemic bias). Minority status is linked to proximal sources of stress through distal stressors (internalized negative feelings: hypervigilance, concealing identity, internalized stigma). Minority group members experience disproportionate health risks due to chronic exposure to both proximal and distal stressors. Intersectionality Theory:Explains how interlocking social "super-structures" (e.g., race, gender, class, sexual orientation) overlap, producing compounded tiers of extreme oppression or privilege. 7. Structural Interventions & Environmental Levels (Swinburn et al., 2002)Structural Intervention: Modifying the physical, legal, economic, or regulatory environment so health-promoting behaviors become the default, natural option. Micro-Environments vs. Macro-Environments:Micro-Environments (Proximal / Direct): Immediate settings and local resources. Examples: Parents serving high-fat diets; peer pressure against physical activity; unhealthy school lunch menus; lack of neighborhood parks/green spaces. Macro-Environments (Distal / Systemic): Broader regulatory and societal infrastructure. Examples: Absence of municipal sidewalks; national agricultural policies funneling subsidized commodity fats/sugars into school systems; absence of federal regulations on junk food advertising to children. Chapter 10: Social Network Theory (SNT)1. Foundations of Social Network TheoryCore Premise: Information, ideas, attitudes, and behaviors spread through interconnected networks of nodes/actors. Analytical Scope: Applies to micro-levels (dyads, triads, small groups) all the way up to macro-levels (organizations, entire industries, nation-states). Historical Development: Conceptualized in the late 1800s; modernized by Mark Granovetter’s 1973 landmark paper "The Strength of Weak Ties". Applied broadly in public health to address smoking, HIV risk, obesity, and community violence. Three Core Assets of Network Models:Communication: The transmission mechanism driving the spread of ideas. Information: The substance/content circulating through the network structure. Relations: The ties and connections binding two or more actors/nodes together. 2. Network Properties & Structural ConceptsActor / Node: Any discrete unit forming a connection (an individual person, clinic, school, corporation, or state). Dyad & Triad: Linkages connecting two nodes (dyad) or three nodes (triad). Homophily: "Birds of a feather flock together"—the tendency of individuals with similar sociodemographic, cultural, or behavioral traits to form ties. Mutuality (Reciprocity): The give-and-take, bidirectional nature of a relationship. Transitivity: The likelihood that two individuals connected to a mutual friend will also connect directly (forming a closed triad).Structural Holes: Gaps or missing links between two individuals or clusters who could otherwise share valuable communication or resources. 3. Centrality & Density MetricsDegree Centrality: The total number of nearest neighbors (direct connections) an actor has that do not pass through any other person. Reflects local popularity and direct exposure. Distance: The number of connections and paths required to travel between two nodes. Closeness Centrality: The average distance from a starting node to all other reachable nodes in the network. Measures how quickly information from that node can diffuse to the entire group. Betweenness Centrality: Measures how often an actor falls along the shortest path between other pairs of nodes. These actors function as critical liaisons, bridges, or gatekeepers. Density: The ratio of actual ties divided by the total possible ties in a network:$\text{Density} = \frac{\text{Actual Observed Ties}}{\text{Total Possible Ties}}$ Dense networks share norms rapidly; sparse networks are fractured and slower to adopt behaviors. 4. Health Dynamics & The SuperdiffuserSmoking Clustering (Christakis & Fowler, 2008): Smokers predominantly form ties with other smokers, driving progressive network-level segregation. Homophily vs. Induction:Homophily (Selection): People choose to associate based on pre-existing shared traits. Induction (Contagion): One member of a network actively influences the beliefs, attitudes, or behaviors of another person after the tie exists. The Superdiffuser: A key member of a homophilic network who sets norms and drives behavior change. Defined by three core traits: Connectivity: Broad social reach; ability to build bridges across distinct groups. Persuasiveness: Innate interpersonal skill and drive to convince others. Mavenism: Possessing recognized, trusted domain expertise in a specific subject area. 5. Network-Individual-Resource (NIR) ModelExplains how social and sexual networks influence HIV transmission and risky behaviors. Posits that individuals and their networks rely on:Mental Resources: Trust, social capital, emotional support. Tangible Resources: Partner income, access to medical care, family physical health. Four Postulates:Resources enable surviving and thriving. Resources satisfying immediate, pressing survival needs take precedence over long-term prevention. Social networks act as tangible and intangible resource banks. HIV and risk-taking spread through network resource dependencies. Chapter 11: Diffusion of Innovations (DOI) Theory1. Introduction to DOICore Concept: Behavior change spreads through a population as a socially contagious process. Self-Sustaining Tipping Point: DOI interventions become self-sustaining once a critical threshold of individuals adopts the innovation. Definition of Innovation: A product, practice, or behavior that is perceived as new by the target group. 2. The 12 Characteristics of an InnovationThe likelihood and speed of adoption increase as an innovation satisfies more of these 12 criteria: Before Adoption:Compatibility: Aligns with prevailing cultural values, customs, and existing practices. Communicability: Easy to explain, teach, and discuss with clarity. Impact on Social Relations: Does not disrupt existing social customs or standing. Relative Advantage: Perceived as substantially superior to what it replaces (socially, physically, or financially). Reversibility: Users perceive they can drop the innovation and return to their baseline without high penalties. Risk and Uncertainty Level: Guaranteed to be low risk yet reliably effective. Trialability: Can be tested on a limited, low-cost basis prior to long-term adoption. During Adoption:

8. Complexity: Easy to perform, understand, or operate (low complexity = high adoption).

9. Time: Demands minimal time investment to learn and incorporate. After Adoption:

10. Commitment: Requires minimal ongoing maintenance, resources, and effort.

11. Modifiability: Can be adapted, customized, or updated as user needs change.

12. Observability: Results and practical use can be clearly seen by peers in the social system. 3. The Four Fundamental Elements of DiffusionThe Innovation: The new practice, tool, or behavior. Communication Channels:Formal Channels (Mass Media): TV, radio, print, internet; best for rapidly generating initial awareness and basic knowledge. Informal Channels (Interpersonal): Direct peer conversations; relies heavily on homophily to build trust and persuade. Time: The speed at which individuals move through the 5-stage innovation-decision process (Knowledge $\rightarrow$ Persuasion $\rightarrow$ Decision $\rightarrow$ Implementation $\rightarrow$ Confirmation). The Social System: The bounded community, cultural norms, and structural boundaries within which the innovation spreads. 4. Rogers' Five Adopter CategoriesInnovators Early Adopters Early Majority Late Majority Laggards

(2.5%) (13.5%) (34%) (34%) (16%)

Innovators (2.5%):The "spark" igniting adoption. High risk tolerance, venturesome, willing to deviate from social norms. Early Adopters (13.5%):Well integrated into communication structures; highly respected, admired, and serve as opinion leaders. Their endorsement legitimizes the innovation, triggering a rapid diffusion cascade. Early Majority (34%):Pragmatic individuals who take longer to weigh decisions than early adopters. Their adoption provides the massive critical mass that proves population-level success. Late Majority (34%):Skeptical and reluctant; have homogeneous networks with limited information sources. Adopt primarily due to overwhelming peer pressure, economic necessity, or because older options are discontinued. Laggards (16%):Extremely traditional, change-resistant, and isolated from opinion leaders. Have prolonged decision periods or never adopt. 5. Take-Home Implementation Rules for DOIWorks best when adoption can be publicly observed and communicated to peers. Works best when the innovation does not require daily, repeated adherence (e.g., a one-time vaccine is easier to diffuse than daily exercise). Efficiently scales up population-level behavior change.