Module 2 Flashcards
Linds experiment:
an early RCT with low participants. sailors given different acidic foods to see if people would recover from scurvy
Why is establishing causal relationships important
- provides support for evidence -based practice
- epidemiology does not determine the cause of disease in individuals rather populations
- enables preventative measures to be put in place even if the cause of a disease isn’t fully understood
Bradford Hill Criteria
7 criteria to help determine if there is a causal relationship (not a checklist)
- temporality
- strength of association
- reversibility
- biological gradient
- biological plausibility of association
- consistency of association
- specificity of association
temporality - bradford hill
did cause come before disease?
Strength of association - bradford hill
RR and RD high? absence of biases (selection, confounding, information)
reversibility - Bradford hill criteria
does change in exposure change the outcome under controlled circumstances?
Biological gradient - bradford hill
does incremental increase of dose response (exposure) result in corresponding increases in outcomes?
biological plausibility - bradford hill
does it make sense biologically (ie chemicals in tobacco are carcinogenic)
Consistency of association bradford hill criteria
replication of findings. multiple studies with similar results in different environments, times, places, methods
specificity of association
a cause leads to a single effect or effect has a single cause
Epidemiological triad:
host: persons in P
Environment: physical, social, policy
Agent: biological, chemical, physical, nutritional
Causal pie - whole pie
sufficient cause- several components, minimum set of conditions for a disease to occur - without any slice, disease unlikely to occur. not a single factor. a disease can have several pies.
causal pie - component cause
a slice of the pie - a factor that contribute sot disease but not sufficient to cause disease on it’s own. includes necessary cause
necessary cause - causal pie
a component cause that must be present in the pie for a disease to occur
counterfactual causation
cause makes a difference in outcome, includes deterministic and probabilistic
probabilistic causation
cause increases the chance that effect will occur. Sufficient raise probability from 0 to 1; necessary raises from 0; each component contributes towards 0 to 1
Deterministic causation
whenever A occurs, B occurs
problems with causal pie model
- assumes all causes are deterministic
- fails to capture dose response as a continuum
Public health framework
Phase 1: define the problem
Phase 2: identify risk and protective factors
Phase 3 Develop and test prevention strategies
Phase 4: ensure widespread adoption
Causes of causes for individual:
any event, characteristic or definable entity that brings about a change for better or worse in health, like income, debt, employment, education, housing
Causes of the causes for population
similar for individuals, but nature and measurement of the determinants are slightly different. Determinants in populations are related to the context that the population exists in
Upstream
distal, a macro. government policies and trade agreements, cultural, legal, national. cause the need for proximal
distant in time or place from the change in health status
Downstream
proximal, micro. treatment and disease management
near to the change in health status
Levels of the Dahlgren and whitehead model
- individual: choices, and non-modifiable factors like age, sex, constitutional factors, and
- community and living conditions: social and community networks. Family and friends play a significant role in developing normative behaviours - what is normal and acceptable to d and experience. also the conditions you live and work in
- environment: general socioeconomic cultural and environmental conditions
habitus
lifestyle, values, dispositions, and expectations of particular social groups, learned through everyday activities
Social capital
Social capital - the value we place on our networks that facilitate bonds and change. who you know not what you know. the community environment and your role in it (ie volunteerism)
level 3 of dahlgren and whitehead - environment
- Physical: water quality, clean air, living things
- Built: design of communities, infrastructure
- Cultural: knowledge, beliefs and values
- Biological: emerging or re-emerging toxins in population
- Ecosystem: climate change, biodiversity, ecological footprint
- Political: policy and approaches to improving pophlth
Properly Built Castles Benefit Every Peasant
3 High level component of living standards frame work
- Individual and collective wellbeing: resources and life aspects important for individuals, families, communities
- Institutions and governance: the role of institutions in safeguarding and building wealth and health
- The wealth of NZ: literal wealth, but also the natural environments, and things not in an accounts
4 capitals
- Natural: environment
- Social: norms and social values, law and trust, crown-maori relationships
- Human: skills and knowledge, mental and physical health
- financial/physical: money, but also infrastructure, housing, etc.
Structure
social and physical environment conditions that influence choices and opportunities available - social factors and choices
Agency
the capacity of an individual to act independently to make free choices
SEP- socio economic position
the social and economic factors that influence what positions individuals or groups hold within a society’s structure.
objective, measurable, meaningful measurements
why measure SEP?
Quantify inequality;
highlight changes over time;
understand relationship between health and other variables;
associations between different chances in life
How measure SEP for individuals
education (quantity and quality);
income;
occupation;
housing;
assets and wealth
How measure sep for populations
area:
- deprivation (i.e decile)
- access
populations:
- income inequality
- literacy rates
- GDP per capita
SEP individual - dahlgren and whitehead
Individual education, occupation, income, decisions these influence your opportunities
SEP community and social - dahgren and whitehead
PARENTS education, occupation, income. Used to measure SEP in children and adolescents. Your parent’s SEP can be associated with your own. This also applies to your friends
SEP Living and working conditions - dahlgren and whitehead
measures like
- NZDep (NZ index of deprivation),
- index of multiple deprivation (IMD) which explores the drivers of area deprivation;
- geographic classification for health (GCH), that classifies based on pop size, and drive time to closest major, large, medium, and small urban areas; social fragmentation and accessibility
Area deprivation
a state of observable and demonstrable disadvantages relative to the local community or the wider community , society, nation to which an individual, group or family belongs
SEP general socio-economic, cultural, environment - dahlgren and whitehead
Global determinants: income inequality, gdp, literacy rates; free trade agreements
group populations with similar SEP together; cross section or longitudinal analyses; NZ census mortality study
preston curve
describes relationship between increase in life expectancy according to decreasing deprivation measures
NZdep 2018 variables
- communication: no access to home internet
- income: 16-64 receive benefit
- income: living in equivalised homes with below threshold income
- employment: 18-64 unemployed
- qualifications: 18-24 without qualifications
- owned home: not living in own home
- support: <65 living in single parent family
- living space: equivalised homes below bedroom occupancy threshold
- living condition: people living in dwellings that are damp or mouldy
Equality vs equity
equality - everyone gets the same
equity - every gets what they need
Inequality
measurable differences in health outcomes and experiences according to groups like SEP, area, gender, ethnicity, race, class
inequity
inequalities that are unfair or stemming from some form of injustice. Differences where the distribution of resources does not reflect health needs - equal and unequal power
PROGRESS acronym
a framework to describe the factors that can contribute to health inequities:
* Place of residence
* race/ethnicity/culture/language
* occupation
* gender/sex
* Religion
* Education
* Socioeconomic status
* Social capital
Also disability is there
MOH inequity definition
in aotearoa new zealand, people have differences in health that are not only avoidable but unfair and unjust
measures of association for inequity
CGO is typically the most advantaged group
* No association: RD-0, RR-1
* Negative association: RD<0, RR-<1
* Positive association: RD->0, RR->1
why reduce inequities?
- they are unfair
- they are avoidable
- they affect everybody
- reducing can be cost effective
lorenz curve
- Order pop. from lowest to highest and ask what % of wealth is owned by poorest 10,20,30%,..etc.
- Draw 45˚ line of absolute equality
- Draw line based on available date = concave
- More concave = greater inequality
Gini coefficient
ratio between the area between perfect equality line and observed lorenze curve to the area between line of perfect equality and line of perfect inequality. = a/a+b. 0 = every equal, 1 = very unequa
implications of inequality
less social cohesion;
less trust;
increased stress;
reduced economic productivity;
poorer health outcomes
commercial determinants of health
the Structures rules, norms, and practices that business activities designed to generate wealth and profits influence population health - the inherent tension between commercial and public health objectives around consumption, accessibility , and affordability
- outer layer of dahlgren and whitehead
Strategies used by commercial industry to impact health
- Shape evidence
- employing narratives and framing techniques
- constituency building
- policy substitution
commercial industry shaping evidence
- lobbying
- shaping research and funding priorities
- financing university programmes, researcha nd chairs
Employing narratives and framing techniques (commercial strats)
- focus on youth (schools)
- focus on individual behaviours
- frame themselves as ‘being part of the solution’
- focus on corporate social responsibility
constituency building (commercial strats)
promoting or sponsoring efforts like charities or health/education related orgs./foundations beyond their core business
policy substitution, development, implementation (commercial strats)
partnerships/voluntary agreements with governments or contributing to health policy consultations
Access definition
the end result of a process flowing from predisposing characteristics and enabling resources (potential access) through need (perceived and evaluated) to ultimate health outcomes (health status and satisfaction)
5 As
dimensions of access - a set of specific areas of fit between patient and healthcare system
availability
accessibility
accommodation
affordability
acceptability
Availability
relationship between volume and type of existing services to the clients volume and type of needs
- ability to get care when need it or in emergency
- one good doctor to treat family
- knowledge of where to get care
- existence of services barriers
accessibility
the relationship betweent he lcoation of supply and the location of clients (considering client transportaion - resources/services, time, distance, cost)
- geographic barriers
- how difficult to get to physicians offices
accommodation
relationship between manner supply resources are organised and expectation of clients (organisation vs expectation)
- wait times
- office hours
- ability to get in touch
- organisational barriers
acceptibility
relationship between clients’ and providers’ attitudes to what constitutes appropriate care
- office appeaance
- office neighbourhood
- other patients
- psychosocial barriers
affordability
cost of provider services in relation to client’s ability and willingness to pay for these services
- satisfied with health insurence
- satisfied with doctors’ prices
- satisfied with when to pay bill
- financial barriers
potential access
what services are available
realised access
what services are actually used and why only those and not others?
Key indicators of maori health status
- life expectancy: gap between maori and non-maori that has not drastically changed since 1951
- deprivation: maori under represented in least deprived and over represented in most deprived deciles
- major causes of death: diabetes, cardiovascular disease higher in maori
- general patterns of mortality and morbidity
historical process that has influenced maori and wellbeing
- colonisation (different values and assumptions colonists; only european view early on)
- tiriti implications (who gets to vote, justice system, land confiscation, colonial values implanted, land ownership)
- land alienation (social disruption, breakdown of political power, lace of capital, led to lower numbers of child survival)
- policy alienation
- unfair citizenship (poverty, dependency, barriers, victim blaming, resentment, social breakdown then high risk behaviour)
how social and economic inequalities between maori and non-maori have arisen
- differential access to health determinants or exposures leading to differences in disease incidence
- differential access to care (access to vaccines)
- differences in quality care (maori not getting preventative inhalers as well as relievers)
interventions
structural - (more life boats, no barriers)
social - (rights based approach - commitment review and level playing field
these aren’t aimed at individual behaviour (e.g swimming lessons)
key sources of data for epidemiology
Census
ERP
Vital events - births, deaths marriages
Health service utilisation
Integrated data infrastructure
nationally represented surveys
ad hoc surveys
estimated resident populations (ERP)
estimate of all people who usually live in NZ at a given date
dependency rations
Dependency is those who are dependent on the working age population
Child = 0-14 years / working age x 100
Elderly = ≥65/working age x 100
Total = (youth+elderly)/working age x 100
Change in dependency ratio will need to be reflected in health system (more elderly = more deaths
natural decline of pop.
occurs when more deaths than births in pop. (more elderly, more deaths)
absolute decline of pop.
occurs when there is insufficient migration to replace lost births and increased deaths
stages of demographic transition
- pre-transition/ industrial - low tot. Pop., vari. Dth rate. High bth rate
- Declining mortality and high bth rate
- Fertility rates decline as pop increase
- High tot. Pop., low fertility, low death rate
ecological fallacy
The error that arises when information about groups of people is used to make inferences about individuals (we use individual data, but measure averages and make conclusion fro that, not the individual because we cannot make conclusions of the individual based on the group and the other way around
Healthy environment
physical social or political setting(s) tat prevent disease wile enhancing human health and wellbeing
- Clean air and water
- Appropriate housing
- Access to wholesome food
- Safe community spaces
- Transport and opportunities to exercises
Built environment
all the buildings, spaces and products that are created,
or at least significantly modified by people
built environment measurements
must be context specific
1. urban density - population or employment
2. land use mix - increases opportunities for active transport
3. street connectivity - encourages active transport
4. community resources, spaces - healthier foods, more opportunities for physical activity
Sustainable development goals
Layer 1 - environment
layer 2 - society
layer 3 - economy
topped by partnerships for the goals
4 V’s of big data
volume - computing capacity for storage and analysis
velocity - data creation and analysis speed
variety - type of data sources available
veracity - accuracy and credibility
also:
variability - consistency, reproducibility
value - cost and value put in
visualisation - use of novel techniques in communication
