EPIDEMIOLOGY Flashcards
Total Hip Replacements (THR) undertaken for two main reasons
→ fracture of neck of femur, emergency -20% of all cases
→ osteoarthritis of hip joint, elective - 80% of all cases
Define need
Condition susceptible to benefit from treatment
Define demand
Treatment for which people are prepared to pay in a market
Define supply
Treatment which is actually provided
In a perfect world Need=Demand=Supply, but imbalances can occur for many reasons. List 4 broad reasons
- Increased needs/demands (aging pop., medical/technological progress, rising expectations). 2, Demands are affected by cultural, social and educational factors
- Needs are affected by current research agendas
- Supply limitations (restraints on resourcese.g. money, time, space)
When Need>Supply what does this create?
Unmet need
What does an unmet need cause within healthcare? 4 listed
Low patient satisfaction
Emergency presentations
Patient suffering, morbidity and morality
Pressure on other services
When need>supply there is an unmet need. This gives rise to the need for rationing. List the 4 types of rationing within healthcare
- Implicit
- Explicit
- Rational
- Irrational
What is the problem with rationing in the NHS?
Contradicts NHS’s founding principles: Comprehensiveness Equal accesss Free at point of need Universality
Describe and explain the 4 types of need
1) Felt need – patient defined
2) Expressed need – patient expresses need to a medical professional
3) Normative need– endorsed by medical professional
4) Comparative need – defined at a population level (vs. another population)
Give example of felt need
`I’ve got a bad pain in my hip, which I would like to get rid of.…’
Need expressed by individual - does not take professional views into account -may be culturally determined/influenced
Give example of expressed need
`I’ve got a bad pain in my hip… doctor, can you do something about it..? ’
Felt need which has been expressed, by making a demand upon health service -does not take professional views into account
Explain normative need with example
Defined by experts. A need endorsed by professional(s) – should be related to evidence base.
`I saw your patient today in my clinic… She has severe osteoarthritis of the hip and would benefit from a total hip replacement….’
May involve assessment of severity. Cultural influences may still be important. Serving gatekeeper function
Explain comparative need with example
Need compared between populations. e.g. Population A has total hip replacement rate of 10/1000/year. In Population B, rate is 6/1000/year - therefore Population B has an unmet need of 4/1000/year….. Is this a reasonable assumption?
This type of need is based on concepts of fairness/equity. May or may not link closely to felt need and expressed need in the individual
Need vs demand vs supply in healthcare
Need: defined on basis of what health care people can benefit from (i.e. is effective)
Demand: treatment which people would wish to use (or be prepared to pay for)
Supply: treatment actually provided
These do not always match in practice
Define health needs assessment
Systematic method for reviewing health issues facing a population, leading to agreed priorities + resource allocation that will improve health + reduce inequalities
What are the 3 elements of a health needs assessment?
- Epidemiological: which interventionsare helpful?Which patient groupsdo intervention work in?
- Comparative: compare service use to use in other comparable areas
- Corporate: consults to assess local public priorities & expert opinion
At least one proper RCT = Type __ evidence
1
Who is involved in a corporate needs assessment?
Purchaser Provider Professionals (hospital, community, GPs) Patients Press Public Politicians
What are the reasons why total hip replacement (or general treatment) provision could vary between locations? 5 points
DIFFERENCES IN:
- Data quality in different settings, so reliability + completeness differ
- Disease prevalence, reflecting differences in population age + sex structure
- Case ascertainment, diagnosis, criteria for operation in different settings
- Resource availability (staff, beds, theatres)
- Healthcare priorities (high/low rates of other conditions
How does data quality affect provision of treatment X in 2 different locations?
Differences in data quality about treatment X in different settings means that reliability + completeness differ
How does disease prevalence affect provision of treatment X in 2 different locations?
Differences in disease prevalence in 2 locations, reflecting differences in population age + sex structure = differences in how many people get treatment X in each location
How does diagnosis affect provision of treatment X in 2 different locations?
Differences in case ascertainment, diagnosis and criteria for operation in different settings will causes differences in numbers of people receiving treatment X
How does resource availability affect provision of treatment X in 2 different locations?
Diffeerences in resource availability (staff, beds, theatres) in 2 locations affect the number of people getting treatment X
How do other conditions affect the availability of treatment X in 2 different locations?
Different healthcare priorities as a result of comparatively high or low rates of other conditions
Give 4 reasons why imbalances occur in need/supply/demand
→ ageing population
→ medical progress
→ new technologies
→ rising expectations
What has been the coventional NHS approach to rationing?
Waiting lists
Give examples of implicit rationing
Waiting lists
Delaying referral based on criteria
Give examples of explicit rationing
Do not provide service at all on basis of criteria
NICE/local NHS agencies
Describe rational rationing
Remove ineffective treatments
Apply criteria consistently
Treat all patients who will benefit
Describe irrational rationing
Rationing on criteria other than effectiveness and cost effectiveness e.g. pt criteria unrelated to outcome.
Locally defined criteria, conflicting with evidence
Describe inequalities in health
Systematic differences in health of groups of people according to:
→ social position → place of residence → ethnicity → sex → other characteristics
Health differences by age not usually referred to as inequalities
How do we measure social status? 5 points
Wealth Occupation Income Housing Amenities (e.g. car ownership)
5 key points about the social gradient in disease (that disease and morbidity decrease with higher social standing)
- Large enough to have appreciable effect on life expectancy
- Applies to women + men
- Differences in mortality occur across life course (perinatal, infant, child, adult)
- Gradient in morbidity as well as mortality
- Apply to wide range of serious chronic diseases + risk factors for diseases
How are geographic inequalities the same as social inequalities in health?
- Affect men and women, impact on life expectancy
- Tend to apply across life course (perinatal, infant mortality onwards)
- Major chronic diseases affected (CVD, cancers, respiratory disease)
- Reverse pattern for breast, skin cancer - ?due to starting family later, increased skin exposure in affluent areas
- Affect morbidity as well as mortality
What are the 6 possible explanations for inequalities in health?
- artefact
- social selection
- differences in behaviour/`lifestyle’
- psychosocial pathways
- differences in material circumstances
- differences in health service provision + use
How could differences in social class be an artefact to health inequality?
Error in ascertaining social class Selection of occupations into social class groups is arbitrary. This is not actually the case - similar mortality seen when comparing housing to mortality.
Describe how feelings of inequality can lead to adverse health conditions
Leads to feelings of inferiority and unfairness or injustice. These give rise to emotional distress + negative feelings, which in turn have physiological effects, usually via neuroendocrine pathways.
Particularly implicated:
- Work-related stress
- Societal level stresses
Some evidence supporting psychosocial factors but overall remains inconclusive
What is the inverse care law?
Health services tend to worsen in locations where it is needed more
Does poor health lead to reduced social class?
Very limited.
a. There is some evidence e.g.mental illness often have a decline in social position
b. Generally a decline in health does NOT cause a decline in social position
What accounts for most of the health inequalities between social classes?
Difference in material circumstances- different employment and living conditions
4 explanations for health differences in ethnic minorites
i) Biological - genetic/hormonal differences
ii) Employment differences
iii) Behavioural differences(smoking + alcohol)
iv) Differences in health service use
How can inequalities in health be reduced?
Most actions lie outside remit of health services. Limited evidence base to guide interventions
Key NHS actions include:
- Establishing equitable access to effective care as a priority
- Reallocating funds to reflect needs of socially deprived population groups
- Improving monitoring of social, geographic + ethnic differences in health
