I&P 1 Flashcards
(cause in epidemiology) What is a Necessary cause?
Presence is required for the occurrence of the event. (cant have disease without exposure, but exposure doesn’t always lead to outcome)
(cause in epidemiology) What is a Sufficient cause?
A factor whose presence leads to an effect (other exposures may also induce the same outcome)
What are inequalities in health?
Variation in health status, life expectancy, mortality & morbidity between different groups. They are systemic differences in healththat are judged to be avoidable by reasonable action.
What are some key health-related demographic events and processes?
Birth, marriage, migration, aging and death.
To calculate birth or fertility rate, why is mid-year population used?
Because populations are constantly increasing, so mid-year is approximately average.
What is period life expectancy?
At a given age for an area is the average age a person would live.
What is cohort life expectancy?
Life expectancy calculated using age-specific mortality rates that allow for projected changes in mortality in later years.
In population pyramids, what does it look like for:
a) Rapidly growing population
b) Slowly growing population
a) Widening base and narrowing middle/top
b) Bands at base narrower than those in middle due to lower fertility rate
What is the natural increase?
The difference between the birth and death rate (demographic transition)
What are the 4 stages of demographic transition?
Stage 1: Birth rates and death rates high (population size stable)
Stage 2: death rates fall as improvements in society, birth rates still high. (population grows)
Stage 3: birth rates fall (land shortages, education for women, family planning), population grows but at a declining rate.
Stage 4: birth rate joins death rate at a stable low rate (population size stable)
What is sex ratio?
Number of males per 100 females born
What is Maslow’s Hierarchy of Need?
- Physiological (breathing, water, sleep etc)
- Safety (security of employment, family, property)
- Love/Belonging (friends, family)
- Esteem (confidence, respect of and by others)
- Self-actualization (morality, creativity, problem solving etc)
(need, supply & demand)
Example of Need but no demand or supply?
Family planning & contraceptive services in many low income countries
(need, supply & demand) Example of Demand but no need or supply?
Patients demanding expectorants for coughs & colds
(need, supply & demand) Example of Supply but no need or demand?
Routine health checks for over 75 year olds
(need, supply and demand) Example of Need and demand but no supply?
Help programmes for substance misuse
(need, supply and demand) Example of need, supply & demand?
People with insulin-dependent diabetes demand insulin, it is effective (need) and it is supplied.
What are 3 types of health needs assessment?
1) Epidemiological (measure health status of population and evaluate means of addressing identified health problems)
2) Comparative (compare with service provision in similar populations)
3) Corporate (ask experts)
What are some methods for recording evidence of population health?
(gets better as you go down list)
- Anecdotes and case series
- Cross Sectional survey
- Counterfactual method
- Ecological studies
- Case-control study
- Cohort study
What are some pros and cons of Cross-sectional surveys?
(count number of people with a disease in a short time period in a pre-defined population)
Pros: quick, good at estimating PREVALENCE
Cons: cannot estimate INCIDENCE, only represents that point in time
Difference between PREVALENCE and INCIDENCE?
Prevalence= cases of disease that are present in the group Incidence= new cases of disease
How can one measure incidence?
A register is commonly used. Records new cases in a pre-specified population
How can incidence be decreased in a population?
By prevention of the disease. If a non-infectious disease could suddenly be cured, then incidence would stay the same.
Pros and cons of Ecological studies?
OBSERVES groups of people- not individuals
Pros: cheaper, less bias, provides new potential risk factors
Cons: ecological fallacy (do population-level measures hold for the individual?), lots of assumptions.
What is a cohort?
People who share a common experience or condition, birth cohort, smokers.
Pros and cons for a cohort study?
followed through time for the outcome- looking at who is exposed or not
Pros: direct measurement of incidence, can look at multiple outcomes.
Cons: Inefficient for rare diseases, expensive.
What is a randomised controlled trial?
(strongest epidemiology method if done correctly- gold standard)
Randomise study population to assign people to treatment group or control group
Follow groups through time & then look at rate of outcome for both
What are the different kinds of blinding?
- Patient doesnt know if they are having treatment or not
- Clinician doesnt know what the patient is having
- Analyst doesn’t know what drug A or B is
What are some potential sources of error?
Study design
Sample collection
Lab analysis
Data analysis/ management/ collection
What are the 3 categories of prevention?
Primary – preventing the onset of the disease, e.g. behaviour/ environment >immunisation
Secondary – halt progression once started, e.g. early diagnosis/ screening
Tertiary – limit disability and complications in established disease (long term), e.g. rehabilitation
What is Geoffrey Rose’s single population theory?
1) Population-wide prevention
2) Target high-risk subjects
What is Derek Wanless ‘Securing our future health’ 2002?
An economic analysis on burden of ill health (imbalance between national sickness service to national health service)
Must be a realignment of incentives therefore.
What is lead time bias?
Early diagnosis falsely appears to prolong survival (only identifies disease early rather than increasing survival)
What is length time bias?
Screening over-represents less aggressive disease (as people with more aggressive disease may be missed- maybe through death). And so makes screening look better.
What are some of the Wilson and Jungner principles of screening for a disease?
- The condition sought should be an important problem
- There should be an acceptable treatment for patients with the recognised disease
- There should be a suitable test for it
- The cost of case-finding should be economically balanced in relation to the possible expenditure
The main causes of childhood mortality?
Pneumonia (18%), preterm complications (14%), diarrhoeal diseases (11%), intrapartum related complications (9%) and malaria (7%).
What 3 strategies did the Ottawa Charter identify for health promotion? (‘the process of enabling people to increase control over and to improve their health)
o Advocating for health (to create the essential conditions for health)
o Enabling people to achieve their full health potential
o Mediating between the different interests in society [in pursuit of health]
What are the 4 health promotion disciplines?
1) Fiscal (tax or subsidy, making healthy things relatively cheap)
2) Legislative (making participation in some unhealthy or risky activities illegal)
3) Service provision
4) Education
