Module 3: Identifying Determinants of Determinants of PopHlth Flashcards
What is socio-economic position (SEP)
The social and economic factors that influence what positions individuals or groups hold within the structure of a society
Socio-economic position aka…
Socioeconomic status
Social class
Social stratification
All have diff theoretical bases and interpretations
Socio-economic determinants must be…
Objective
Measurable
Meaningful
Purpose of measuring SEP
Quantify level of inequality within or between societies
Highlight changes to pop structures over time, e.g. between Census periods and generations
Help understand relationship between health and other social variables
Types of SEP measurements for individuals
Education Income Occupation Housing Assets and wealth
Types of SEP measurements for populations
Area measures:
- Deprivation
- Access
Population measures:
- Income inequality
- Literacy rates
- Gross Domestic Product (GDP) per capita
SEP: Dahlgren & Whitehead Model - Individual lifestyle factors
YOUR education, occupation, income You and the decisions you make influence your opportunities: Education --> knowledge Income --> material goods Occupation --> status, power
SEP: Dahlgren & Whitehead Model - Social and community influences
Your parents’ education, occupation, income etc
Commonly used to measure SEP in studies of children and adolescents
Some evidence that parents’ SEP is associated with individuals’ SEP
SEP: Dahlgren & Whitehead Model - Living and working conditions
Area-based measures of SEP:
- NZ Index of Deprivation (NZDep) - most common in NZ
- Index of Multiple Deprivation (IMD) - allows you to explore drivers of area deprivation
Other measures e.g. social fragmentation and accessibility indices:
- difference between potential and realised access
Define deprivation
A state of observable and demonstrable disadvantage relative to the local community, wider society or nation to which an individual, family or group belongs
Area-level deprivation measurement
Measures people’s relative position in society, but reports this based on where they live, not who the people are themselves
Focuses on material deprivation - refers to what residents living in particular areas don’t have (deficit model – easier to ask than what people have)
What should deprivation be applied to
Conditions and quality of life that are of a lower standard than is ‘ordinary’ in a particular society
Deprivation – poverty
Living in poverty refers to a lack of income and resources to obtain the normative standard of living
Variables included in NZDep2013
Communication - people aged <65 with no access to internet at home
Income - people aged 18-64 receiving a means tested benefit
Income - people living in equivalised households with income below an income threshold
Employment - people aged 18-64 unemployed
Qualifications - people aged 18-64 without any qualifications
Owned home - people not living in own home
Support - people aged <65 living in a single parent family
Living space - people living in equivalised households below a bedroom occupancy threshold
Transport - people with no access to a car
Equivalisation
Methods used to control for household composition
A form of standardisation
Deciles and quintiles
Deciles: 10 groups
Quintiles: 5 groups
Least deprived of pop = 1, most deprived = 10
SEP: Dahlgren & Whitehead Model - General socio-economic, cultural and environmental conditions
Group populations with similar SEP levels together
Cross sectional or longitudinal studies
NZ Census mortality study
Integrated Data Infrastructure
SEP: Dahlgren & Whitehead Model - Global determinants
Income inequality
National income - GDP
Literacy rates
Free trade agreements – how well our economy is veering between diff markets and how that relates to health outcomes
Causes of causes: access to health care
Belonging to a marginalised group --> Discrimination --> Access to education --> Educational attainment --> Employment status --> Income --> Access to health care
Equivalised households
Demonstrates differences between a 2 person and 20 person household
Population data - measures (trends in)…
Births
Mortality/deaths (all-cause, cause-specific)
Morbidity/illness (general, specific condition)
Migration
Population data - can be applied to…
Unemployment/benefit claimants/pensions
Crime (broad and detailed classes of offence)
Health service utilisation (where to provide and who uses them)
Voter turnout, political party voted for
Education pathways
Main pop data sources for epidemiology
The Census Estimated Resident Populations (ERP) Vital events Health service utilisation and outcomes (HSU) Integrated Data Infrastructure (IDI) Nationally representative surveys Ad hoc surveys
Data source - Census
Traditionally, people were employed as ‘enumeration officers’ to contact individual households to ensure census data collection:
- deliver and collect census form
- check fully completed
- country divided into small areas (meshblocks) with ~100 people on average - designed to be manageable for enumeration officers
2018: went online
Data source - Estimated Resident Populations (ERP)
An estimate of all people who usually live in NZ at a given date
Doesn’t typically break down by ethnic group
Data source - Vital Events
Births, deaths and marriages
Department of Internal Affairs maintain, but Stats NZ prepares report
Data source - Health Service Utilisation and Outcomes (HSU)
Ministry of Health record and report publicly funded health information
e.g. hospitalisations, blood tests, pharmaceutical dispensing
Reflects pop that interacted with health system in last 2 years prior to March 2013
Ethnicity collected from PHO
Data source - Integrated Data Infrastructure (IDI)
Large data repository that links de-identified data about people that have used government services (and some other agencies) e.g. health, education, tax, ACC
Strict rules in place to preserve confidentiality
Data source - Nationally representative surveys
e.g. NZ Health Survey:
- Ministry of Health manages survey with key topics and ‘spotlight’ coverage on less common issues
Self-reported health and health behaviours
Data source - Ad hoc surveys
Student satisfaction survey, market research companies etc
May not always be generalisable to wider pop
Denominators and age-structure
Census < HSU < IDI
HSU distribution - older age groups
Generally at older age groups, populations are quite similar
HSU distribution - students
Students less likely to visit doctors –> may not have visited doctors in past 2 years –> not included in HSU population
However, most would have paid taxes / enrolled in education –> included in IDI population
Data considerations
Ethics and data privacy/confidentiality
Purpose of data collection vs use in analysis
Pop vs pop samples
Are participants representative of NZ pop?
Objective vs subjective measures of health
Demographic terminology: Population by attributes
Population (counts or %) by attributes (variables):
- age
- sex: male/females (biological) vs gender (behavioural)
- other attributes
Population pyramids
X-axis: males on left, females on right
Y-axis: age (single year or grouped in 5 year bands, young at bottom, old at top)
Bars: either count or % of people in each age-sex group
Population structure
Age and sex
Function of previous trends of fertility, migration and mortality events
Changes in fertility and infant mortality rates can be dramatic but will have time lag
Changes in adult mortality rates less dramatic and less variable over time - spread over wider age range
Migration can have dramatic effect, especially if trend is age/sex specific
Population composition
Other attributes apart from age and sex
Population structure - how it affects events
Crucial influence
Fertility, mortality and migration not evenly distributed across pop by age and sex
Fertility: women only, concentration in young adults
Mortality: highest among very young and elderly
Migration: varies with sex and stage in life cycle
Demographic history of an area - time period
1920 - 1945: Mortality decline and increased life expectancy
1960 - 1970: Baby boom
1975 - 1985: Baby bust
1990 - 1995: Baby boom echo
Dependency ratios - age groups
Child: 0-14 years / working age x 100 Elderly: >=65 / working age x 100 Total: (youth + elderly) / working age x 100
Where working age is 15 - 64 y/o - this is a limitation as it is assuming those in working age group are 15-64 y/o
What does ethnic composition of NZ depend on
Data sources for numerator and denominator
Ethnicity coding protocol used
Prioritised output - advantages
Ensure that where some need exists to assign people to a single ethnic group, ethnic groups of policy importance or of small size aren’t swamped by NZ European ethnic group
Produces data that is easy to work with - sum of ethnic group pop adds up to total NZ pop
Prioritised output - disadvantages
May over-represent some groups at expense of others
Externally applied single ethnicity which is inconsistent with concept of self-identification
Total response output - advantages
Has potential to represent people who don’t identify with any given ethnic group, depending on level of detail reported
Total response output - disadvantages
Creates complexities in distribution of funding based on pop numbers or in monitoring changes in ethnic composition of a pop in health
Creates issues in interpretation of data where comparisons between groups include overlapping data
Types of ageing
Numerical ageing
Structural ageing
Numerical ageing
The absolute increase in the pop that is elderly
- reflects previous demographic patterns
- improvements in life expectancy
Structural ageing
The increase in proportion of pop that is elderly
- driven by decreases in fertility rates
Population impacts of ageing
Natural decline of population
Absolute decline of population
Natural decline of population
Occurs when there are more deaths than births in a pop
- combination of absolute and structural ageing
- more elderly = more deaths
Absolute decline of population
Occurs when there is insufficient migration to replace the ‘lost’ births and increased deaths
- not expected to happen in NZ for 70+ years
- happening in some European/Asian countries
Main causes of death in NZ
Cancer Ischaemic heart dis-ease Stroke Chronic lower respiratory dis-ease Other forms of heart dis-ease
Parts of demographic transition
- Pre-transitional / pre-industrial
- Declining mortality, birth rates remain high
- Fertility rates begin to decline
- Low fertility and low mortality
Inequities - political
Pop health is laden with politics
All governments want to improve health and well-being of society, but how improvements can be approached differs widely
Inequalities
Measurable differences in health
Differences in health experience and outcomes between diff pop groups according to SEP, area, age, disability, gender, ethnic group
i.e. the ‘social gradient’
Inequities
Inequalities deemed to be unfair or stemming from some form of injustice
Health inequities are differences in distribution of rss/services across pop’s which don’t reflect health needs
Relations of equal and unequal power - political, social, economic, as well as justice and injustice
Equity - MoH definition
In NZ, people have differences in health that are not only avoidable but unfair and unjust
Equity recognises diff people with diff levels of advantage require diff approaches and rss to get equitable health outcomes
Te Tiri o Waitangi
Focus of all health policy in NZ
Manawhenua
Mataawaka
Privilege
An important part of pop health, but is hard to measure
Association and causality
Association does NOT mean causality
PROGRESS
Place of residence Race/ethnicity/culture/language Occupation Gender/sex Religion Education Socioeconomic status Social capital
+ Disability
Rate difference
i.e. risk difference (RD) - absolute measure
EGO - CGO
Rate ratio
i.e. risk ratio / relative risk (RR) - relative measure
EGO/CGO
Who is CGO
The group being compared to, usually:
- high income group
- NZ European group
Common practice is to use the ‘most advantaged’ group
Measures of association/effect
No association:
Rate diff = 0
Rate ratio = 1
Negative association:
Rate diff < 0
Rate ratio < 1
Positive association:
Rate diff > 0
Rate diff > 1
Why reduce inequities?
They are unfair
They are avoidable
They affect everyone
Reducing inequities can be cost-effective
Unmet needs
Asks survey pop if they’ve been to the gp, and if there’s been a time in the past 12 months they haven’t been able to see a gp in a primary healthcare setting and why they couldn’t
e.g. unmet need for gp services due to cost, unmet need for after-hours services due to transport