Block 8 Flashcards
Define prognosis
an assessment of the future course and outcome of a patient’s disease, based on knowledge of the course of disease in other patients together with the general health, age and sex of the patient
Why is prognosis important?
- knowledge of prognosis with or without treatment can help treatment decisions
- it’s important for patients to understand the likely course of their disease
- different patients will value different outcomes and this will need to be taken into account during decision making
What are prognostic factors?
Characteristics of the patient which can be used to predict outcomes more accurately. They can be:
- demographic e.g. age, gender
- disease-specific e.g. grade of tumour
- co-morbid e.g. other coexisting disease condition
What type of research questions can be asked about prognosis?
- which outcomes could happen? (qualitative aspect)
- how likely are the outcomes to happen? (quantitative aspect)
- over what time period will the outcomes happen? (temporal aspect)
What are the most appropriate study designs for assessing prognosis?
- cohort study
- case-control study
What are the advantages of Cohort Studies?
- measurement of exposure to risk factor is not biased by presence or absence of the outcome
- can provide data on time course of outcome development
- more than one outcome can be examined at once
- useful for investigating rare exposures
What are the disadvantages of Cohort Studies?
- potential for bias due to selection of subjects
- danger of losses to follow-up
- historical studies are dependent on accuracy of records or recollection
- exposure to risk factors/existence of prognostic factors may change over the course of the study
- can be timely and costly to carry out
What are the advantages of Case-Control Studies?
- relatively quick to carry out
- can be used to examine outcomes that are relatively rare
What are the disadvantages of Case-Control Studies?
- problems with possible bias in selection of cases and controls
- potential for recall bias
- measurement of exposure to risk factors may be biased by prevalence or absence of the outcome
How can the likelihood of an outcome occurring over a period of time be presented?
- as a percentage survival/specified outcome at a particular point in time e.g. 40% survive at 5 years
- as median survival; the length of time by which 50% of people have experienced the outcome e.g. at least half of all patients survive 5 years
- as survival curves which depict each point in time the percentage of the original sample who have not yet experienced the outcome
What did the Bisexuality Report 2010 show?
- bisexual peoples experiences differ from heterosexual and lesbian and gay people
- biphobia is distinct from homophobia
- bi people can experience discrimination from within heterosexual, lesbian and gay communities
- bisexual populations have significantly higher levels of distress and mental health difficulties than equivalent heterosexual, lesbian or gay populations
What is heterosexism?
The widespread social assumption that heterosexuality may be taken for granted as normal, natural and right
What is homophobia?
An irrational fear and dislike of lGBT people which can lead to hatred resulting in verbal and physical attacks and abuse
- MSM are ___ times more likely to commit suicide
- LGBTQ young people are ___ times more likely to self harm and ___ more likely to have depression
- Lesbians are ___ more likely to have an eating disorder than women in general
- 4
- 4
- 3
- 4
What were the recommendations of the Stigma Report?
- increase all staff’s capacity for meaningful communication
- all surgeries to develop and prominently display equality policies, statements and guidelines which explicitly include sexual orientation
- to adhere to clear guidelines around confidentiality and patient notes
- require all staff to act according to guidelines
What prohibits discrimination in provision of goods, facilities or services?
The Equality Act 2007
What does the GMC say about personal beliefs in medical practice?
You must not allow personal beliefs that you hold about patients to prejudice your assessment of their clinical needs or delay or restrict their access to care. This includes age, colour, culture, disability, ethnic or national origin, gender, lifestyle, marital status, race, religion, sex, sexual orientation or SES
What is meant by falsifiability?
- scientific knowledge is invariably vulnerable and may be false
- scientific theories cannot be asserted as true categorically but can only be maintained as having some probability of being true
- Popper said that theories that are unfalsifiable are pseudoscience
What are the Bradford Hill criteria?
Factors to consider when assessing causation (TESSERACTC)
- Temporality
- Exposure-response
- Strength of association
- Specificity
- Experiment
- Reversibility
- Analogy
- Consistency
- Theoretical plausibility
- Coherence
What is Temporality? (BHC)
A cause must precede its effect but is all that can be said with any degree of certainty. It does not follow that if exposure to a proposed causative agent precedes an effect that the latter is the direct consequence of the former.
What is Reversibility? (BHC)
Does removal of a presumed cause lead to a reduction in the risk of ill-health? Reduction in a particular exposure if followed by a reduced risk of a particular disease may strengthen the presumption of a real cause-effect relationship.
What is Strength of Association? (BHC)
AKA - effect size
A small association does not mean that there is not a casual effect but the larger the effect, the more likely that it is casual.
What is Exposure-response? (BHC)
AKA - Biological gradient
Is increased exposure to the possible cause associated with an increased response (i.e. an increased likelihood of an effect)? Greater exposure often leads to a greater incidence of the effect, however in some instances the mere presence of the cause can trigger the effect
What is Consistency? (BHC)
AKA - reproducibility
Have similar results been shown in other studies? Consistent findings observed by different persons in different places with different samples strengthens the likelihood of an effect.
What is Theoretical Plausibility? (BHC)
A plausible mechanism between proposed cause and effect is useful in supporting a causal relationship but knowledge of such a mechanism is limited to current understanding, e.g. Is there a reasonable postulated biologic mechanism linking the possible cause and the effect? Could there be a mechanism we don’t yet know about?
What is Analogy? (BHC)
Can parallels be drawn with examples of other well-established cause-effect relationships? The effect of similar factors should be considered.
What is Specificity? (BHC)
Does the cause lead to a specific effect? (i.e. one cause - one effect) The more specific the association between a factor and an effect, the greater the probability of a causal relationship. Only rarely is specificity demonstrable in environmental cause-effect relationships (other than in infectious diseases).
What is Coherence? (BHC)
Consistency between epidemiological and laboratory findings increases the likelihood of a causal relationship. However, Hill noted that lack of lab evidence cannot nullify the epidemiological effect on associations.
What is Experiment? (BHC)
Occasionally it is possible to appeal to experimental evidence. Does an animal model exist? What does it show?
What is medicalisation?
- the process by which some aspects of human life, including social issues and aspects previously considered as “natural”, come to be redefined as medical problems whereas before they were not considered pathological
- e.g. pregnancy, childbirth, death, ageing, sexual desire, unhappiness
Why is there a scarcity of resources in the NHS?
- expensive advances in medical technology
- demographic changes; ageing population
- budgetary restrictions
- public expectations
What is healthcare rationing?
When someone is denied (or simply not offered) an intervention that everyone agrees would do them some good and which they would like to have
What does opportunity cost mean in healthcare systems?
The explicit decision to devote resources to one patient is inevitably an implicit decision to deny them to someone else
Give three principles of rationing healthcare
- rationing by ability to pay
- rationing by “need” or by ability to benefit
- rationing by social values
What were Williams principles to guide rationing?
- treat equals equally and with dignity
- meet peoples needs for healthcare as efficiently as possible so as to impose the least sacrifice on others
- minimise inequalities in the lifetime health of the population
What influences choices about food?
- rational health choices
- cost
- availability
- habit, custom and tastes
- sensuous gratification
- comfort
- emotional and relational needs
- social and cultural constraints
Give examples of social and cultural constraints on food choice
- religious beliefs
- political beliefs
- advertising
- identity
- disease status
What did Willis find about class and food choices?
- middle class families were secure and future oriented and teenagers had less autonomy over their eating
- working class families faced risk and insecurity and were more focussed on the here and now, concerns about food, weight, and health were less pressing than worries about every day life
What is food poverty?
- the term used to describe a form of social exclusion that makes it hard for someone to obtain a nourishing diet
- inability to afford or have access to food to make up a healthy diet
- worse diet, worse access, worse health, and a higher percentage of income spent on food creating less choice from a restricted range of foods
What are the potential reasons for increases in food poverty?
- decline or public transport, particularly affecting older people and single parents with young children
- collapse of independent food retailers and supermarket expansion
- commercial incentive for food manufacturers to push high-fat, low-nutrition food, particularly at the value for money end of the market
- low incomes, making filling foods with high fat content more attractive than fresh fruits and vegetables
What are guidelines?
Statements that include recommendations intended to optimise patient care that are informed by a systematic review of evidence and an assessment if the benefit and harms of alternative care options
Who makes guidelines?
- PHE
- NICE
- CDC
- WHO
- Colleges and Societies
What is the point of guidelines?
- promote consistency, reduce the post-code lottery
- evidence-based so patients get effective treatments
- close the gap between what physicians do and what is supported by evidence
Why might people not adhere to guidelines?
- lack of knowledge of the guideline
- conflicting guidelines (e.g. patients with comorbidities)
- in rapidly developing areas of therapy
- failure to understand/agree responsibility for using the guidelines
What do systematic reviews do?
- evaluate and interpret all the available research relevant to a particular question
- address a specific question
- aim to be rigorous. comprehensive and explicit
- use systematic methods
- are transparent, replicable and open to criticism
What should a systematic review contain?
Presented as a structure report which includes:
- a well formulated research question
- a comprehensive data search
- an unbiased data selection and abstraction process
- a critical appraisal of the data
- synthesis of the data
- an objective interpretation of the findings
- clearly reported methods and results
What components should a good systematic review question include?
PICOS
- population
- intervention
- comparators
- outcomes
- study design
What is the process of conduction a systematic review?
1) formulate review question
2) formulate research protocol
3) literature search
4) study selection
5) data extraction
6) synthesis
7) quality assessment
8) conclusions
Good guidelines are…
- based on systematic reviews
- developed by competent MDTs
- adequate in considering important patients subgroups and preferences
- based on explicit and transparent processes
- transparent in providing ratings of the quality of evidence and strength of recommendations
- reconsidered and revised when new evidence comes up
- kept up to date
What is the difference between systematic reviews and guidelines?
Systematic reviews will address few questions whereas guidelines will address many questions
How can systematic reviews inform guidelines?
- guidelines will need to draw from the results of many systematic reviews
- gaps that systematic reviews do not fill should be filled by other sources of info such as expert opinion
What are the pros of protocols?
- provide a clear framework
- increase autonomy
- ensure consensus
- promote accountability
- identifies training needs
What are the cons of protocols?
- may stifle individual care management
- may reduce need for qualified staff
- requires regular review
- compliance
- may restrict clinical discretion
What makes a good protocol?
- clearly documented lines of accountability
- specific referral criteria
- clarity
- brevity
- fits with professional guidelines
What us a LTC?
A condition that cannot currently be cured but can be controlled with the use of medication and or other therapies
What makes LTC different to other conditions?
- uncertainty: in diagnosis, prognosis and symptoms
- biological and social factors interact
- can impact upon many aspects of people’s lives (identity, relationships, work and finances
- involve high levels of self-care management
LTC can…
- be disabling
- cause intense pain
- cause embarrassment
- cause stigma
How many people live with LTC in the UK?
- 15m (25%)
- likely to rise to 18m by 2025
What are the financial and resource costs of LTCs?
- 70% of health care expenditure on 30% of the population
- 50% of GP appointment
- 65% of outpatient appointments
- 70% of inpatient bed days
