ASBHDS Session 4 - Evidence and Evidence-based Practice Flashcards
What are the origins of evidence-based healthcare?
- Health service delivery should be based on best available evidence
- Best evidence = findings of rigorously conducted research
- Evidence of:
I. Effectiveness (of drugs, practices, interventions)
II. Cost-effectiveness (in a system with finite resources where should money be spent to gain the maximum utility?)
- Ineffective and inappropriate interventions waste resources that could be used more effectively
- Variations in treatment create inequities
- Care that is non-evidence based likely to cause harm
- Practices influenced (too much) by:
I. Professional opinion
II. Clinical fashion
III. Historical practice and precedent
IV. Organisational and social culture
What is evidence based practice?
Evidence-based practice involves the integration of individual clinical expertise WITH the best available external clinical evidence from systematic research.
“Evidence based medicine is not ‘cookbook’ medicine. Because it requires a bottom up approach that integrates the best external evidence with individual clinical expertise and patients’ choice, it cannot result in slavish, cookbook approaches to individual patient care. External clinical evidence can inform, but can never replace, individual clinical expertise.”
Why are systematic reviews needed?
- Traditional, “narrative” literature reviews may be biased and subjective
- Not easy to see how studies were identified for review
- Quality of studies reviewed variable and sometimes poor
- Systematic reviews are useful - can help address clinical uncertainty
- Systematic reviews can also highlight gaps in research/poor quality research
Why are systematic reviews useful to clinicians?
- By appraising and integrating findings, they offer both quality control and increased certainty
- They offer authoritative, generalisable and up-to-date conclusions.
- They save clinicians from having to locate and appraise the studies for themselves.
- They may reduce delay between research discoveries and implementation.
- They can help to prevent biased decisions being made
- They can be relatively easily converted into guidelines and recommendations
- However, doctors need to be able to access systematic reviews and to appraise them to be satisfied about the quality of the evidence
How does one assess the quality of evidence?
- Easiest and best done using a “critical appraisal tool” or instrument
- Critical appraisal tools suggest the things to look for, and the questions to ask of, research articles
What are some of the critiques of evidence-based practice movement?
- Practical criticisms’: around the possibility of evidence-based practice
I. May be an impossible task to create and maintain systematic reviews across all specialities.
II. May be challenging and expensive to disseminate and implement findings.
III. RCTs are seen as the gold standard but not always feasible or even necessary/desirable (e.g. due to ethical considerations).
IV. Choice of outcomes often very biomedical, which may limit which interventions are trialled, and therefore which are funded (e.g. NICE guidance).
V. Requires ‘good faith’ on the part of pharmaceutical companies
- ‘Philosophical criticisms’: around the desirability of evidence-based practice
I. ‘Does not align with (most) doctors’ modes of reasoning (probabilistic versus deterministic causality).
II. Aggregate, population-level outcomes don’t mean that an intervention will work for an individual.
III. Potential of EBM (or its implementation, e.g. through NICE or clinical governance) to create ‘unreflective rule followers’ out of professionals.
IV. Might be understood as a means of legitimising rationing, with potential to undermine trust in the doctor-patient relationship, and ultimately the NHS.
V. Professional responsibility/autonomy
What are the problems with getting evidence into practice?
- Evidence exists, but doctors don’t know about it – Dissemination ineffective? Doctors not incentivised to keep up-to-date?
- Doctors know about the evidence but don’t use it – Why not? Habit? Organisational culture? Professional judgement?
- Organisational systems cannot support innovation – E.g. because managers lack ‘clout’ to invoke changes
- Commissioning decisions reflect different priorities – E.g. what if patients say they want something else?
- Resources not available to implement change – Financial or human resources: change management is a complicated and demanding process
What are key considerations withr regards to resource allocation?
- Setting priorities: scarcity of resources
- NHS spending
- Demand driven by demographics: age<CS
- Costs of new technology
- Setting priorities: scarcity and ethics
What are the two forms of rationing?
- Explicit rationing – based on defined rules of entitlement
I. Explicit health care rationing or priority-setting is the use of institutional procedures for the systematic allocation of resources within health care system.
II. Care is limited and the decisions are explicit, as is the reasoning behind those decisions.
- Implicit rationing – care is limited, but neither the decisions, nor the bases for those decisions, are clearly expressed.
I. Implicit rationing is the allocation of resources through individual clinical decisions without the criteria for those decisions being explicit
II. Can lead to inequities and discrimination
III. Open to abuse
IV. Decisions based on perceptions of “social deservingness”
V. Doctors appear increasingly unwilling to do it
What are some pros and cons with rationing?
- ADVANTAGES
I. Transparent, accountable
II. Opportunity for debate
III. More clearly evidence-based
IV. More opportunities for equity in decision-making
- DISADVANTAGES
I. Very complex
II. Heterogeneity of patients and illnesses
III. Patient and professional hostility
VI. Impact on clinical freedom
V. Some evidence of patient distress
Outline some basic concepts in health economics.
- Scarcity: need outstrips resources. Prioritisation is inevitable
- Efficiency: getting the most out of limited resources
- Equity: the extent to which distribution of resources is fair
- Effectiveness: the extent to which an intervention produces desired outcomes
- Utility: the value an individual places on a health state
- Opportunity costs: once ou have used a resource in one way, you no longer have to use it in another way.
Outline choices and efficiency.
- Technical efficiency – you are interested in the most efficient way of meeting a need (e.g. should antenatal care be community or hospital-based?).
- Allocative efficiency – you are choosing between the many needs to be met (e.g. fund hip replacements or neonatal care?)
Explanation economic evaluations and decision-making.
- Comparison of resource implications and benefits of alternative ways of delivering healthcare.
- Can facilitate decisions so that they are more transparent and fair.
How do you measure costs?
- Identify, quantify and value resources needed
- Categories of costs:
I. Costs of the healthcare services
II. Costs of the patient’s time
III. Costs associated with care-giving
IV. Other costs associated with illness
V. Economic costs borne by the employers, other employees and the rest of society
How do you measure benefits?
- Benefits are harder to measure
- Improved (or maintained) health hard to value
- Categories of benefits/consequences:
I. Impact on health status (in terms of survival or quality of life or both);
II. Savings in other healthcare resources (such as drugs, hospitalisations, procedures, etc.) if the patient’s health state is improved
III. Improved productivity if patient, or family members, returns to work earlier
Discuss the types of economic evaluation.
What is QALY?
- QALYs adjust life expectancy for quality of life
I. 1 year of perfect health = 1 QALY
II. Assumes that 1 year in perfect health = 10 years with a quality of life of 0.10 perfect health
- One year of healthy life for one person
I. You can trade off survival and quality of life
1 QALY = 2 years at 50% QOL for 1 person
II. Each year of healthy life is of equal value
1 QALY = 6 months of healthy life for 2 people
Provide an example of QALY.
- Told he has 1 year to live if he does not have treatment
- His quality of life, without treatment, will be 0.8 of perfect health and he will then die quickly
- Without treatment = 0.8 QALYs
- If he receives treatment he will live for 4 years, but his QoL will be 0.2 of perfect health
- With treatment = 0.8 QALYs
- No gain in QALYS associated with treatment
