Evidence-Based Public Health Flashcards
Define evidence.
Unbiased and scientifically-produced information and
knowledge
What is science?
A systematic enterprise that builds and organises knowledge in the form of testable explanations and predictions about the universe.
What is contemporary science subdivided into?
Natural sciences (studies the material universe) Social sciences (studies people and societies) Formal sciences (studies logic and mathematics)
Why are the formal sciences often excluded?
They don’t depend on empirical observations
What may be considered applied sciences?
Disciplines which use science, like engineering and medicine.
When was the term ‘evidence based medicine’ first coined?
1991
What does EBM call for?
Calls for clinical decisions and treatments to be formalised, transparent and based on high quality ‘scientific evidence’
Why is EBM beneficial?
Would improve the quality of patient care and make health care more affordable (e.g. rid health systems of ineffective treatments).
What is the hierarchy of evidence?
systemic reviews clinical trials (randomised, masked) observational studies (cohort, cross-sectional, case-control) case reports, case series anecdotal findings, opinions, ideas
What are the methodological limitations of EBM? (2)
- Limitations of the RCT
* Design of RCTs: bias, internal validity and generalisability (external validity)
What is the economic limitation of EBM?
• Cost of RCTs
What are the political limitations of EBM? (3)
- Capture by vested interest groups
- Who pays for research?
- What is and isn’t researched
What is another limitation of EBM?
Managerial hubris and deprofessionalisation - the diminution of clinical experience, expertise and judgement.
Real EBM incorporates…? (3)
Individual clinical expertise
Best external evidence
Patient values and expectations
Define ontology.
The study of the nature of being, existence or reality (metaphysics).
Define epistemology.
The study of knowledge
What is methodology? What is it based on?
The principles that guide our research practices – based on what epistemology are we working in, and what our ontological position is.
What does public health focus on? What are the interventions often like?
Populations, communities and societies
Often social or applied through social systems, and tend to be upstream.
What determines health? And to what extent? (4)
Social characteristics/total ecology most important
Health behaviours
Health care
Genes and biology
Why is hard to have evidence-based public health policies? (3)
More complex and difficult to generate
Upstream interventions and downstream effects
Hard to do RCTs
Studying something complex/open/contextual
Explain positivism.
The world exists independently of us, i.e. there is an ‘objective’ stable reality ‘out there’. Through objective scientific methods, we can explain, predict, control
events and phenomena. There is a clear distinction between the ‘subjective’ observer and the
‘objective’ world.
Explain interpretivism.
All reality is viewed, described and understood by a socially-constructed mind. Reality is shaped by history, culture, politics and context – as a result, there are multiple realities and multiple truths. Knowledge obtained by research is partial and situated (i.e. specific to particular situations and periods rather than universally applicable), and is also influenced and shaped by the researcher’s world view and value system.
In the absence of any intervention, transmission rates of HIV from mother to child range from…?
What is it for…
in utero?
during delivery?
post-partum?
15-45%
– In utero: 5-15%
– During delivery: 10-20%
– Post-partum: 10-20%
How can we prevent HIV transmission in adults? (5)
What does this depend on? (8)
- Prevent pregnancy in HIV positive women
- Reduce viral load during pregnancy, childbirth and after
- Avoid amniocentesis
- Promote elective caesarian sections and avoid premature rupture of membranes and delivery
- Avoid breastfeeding
Depends on: Socio-economic context Health systems capacity Economic context Clinical epidemiology Cost and affordability of interventions State of science Political and policy context Priorities emerging/changing
What are the research challenges? (5)
New and fast evolving industry Cost of research Generalisability Time lag Limits to knowledge