Block 3 & 4 Flashcards
Describe three theories of decision making
- normative: what should you be doing, according to social or professional norms?
- descriptive: what are you doing?
- prescriptive: how can we improve what you are doing?
Describe the hypothetic-dedctive model (Elstein 1978)
- seeking evidence to disprove your hypothesis
- cue acquisition > hypothesis formation > cue interpretation > hypothesis evaluation
What did Norman (2005) suggest about diagnostic reasoning?
- hypothetic-deductive model is more commonly used when the clinician has less experience, generally or in that area
- experienced clinicians are more likely to use pattern matching
- experts encountering a less common problem are more likely to use deliberative reasoning
Describe the prospect theory of decision making (Tversky and Kahneman, 1988)
Two phases:
- framing and editing : the preliminary analysis of the decision problem
- phase of evaluation : framed prospects are evaluated and the prospect with the highest value is selected
What three factors can influence the decision making process?
- Framing: how the problem is framed (role of bias)
- Values: a persons values and associated beliefs about the benefits and harms of different options and their outcomes
Evaluation: a persons ability to evaluate the information they have used
Outline the hierarchy of quantitative evidence (best to worst quality)
- Systematic reviews and meta-analyses
- Randomised controlled double blind trials
- Cohort studies
- Case control studies
- Case series
- Case reports
- Ideas, Editorials, Opinions
- Animal research
- In vitro research
Describe how the hierarchy of evidence works and it’s limitations
“better quality” research is higher in the pyramid, it has less potential for bias and so has more predictive power
HOWEVER
- different study designs are suited to different questions
- there are good and bad studies of all types
- the pyramid doesn’t include qualitative research
- it must be used critically
Describe levels of organisation of evidence (5S) and how they fit together
- each stage is condensed into the next
- studies (e.g. original journal articles) > syntheses (e.g. systematic reviews) > synopses (e.g. evidence based journal abstract) > summaries (e.g. evidence based text books) > systems (e.g. computerised decision support)
How can evidence be used in diagnosis?
- to identify the most likely hypothesis
- to evaluate likelihood of hypothesis being correct
- to assess the accuracy of diagnostic tests
How can evidence be used in prognosis?
- to evaluate what happened to other patients with the same condition
How can evidence be used in treatment decisions?
- to evaluate the likelihood of different options having an effect
- to evaluate the likelihood of adverse events happening to the patient
- to assess the likely acceptability of the treatment to the patient
Define consent (MPS)
The properly informed decision of a competent patient, freely given
How can consent be given?
- orally
- written
- expressed
- implied
When is consent required?
- before examination, treatment or care
- for disclosure of confidential information
- when involving a patient in teaching
- research
To be valid, consent must be…
- informed
- voluntary
- given by a patient who has capacity
Why is consent needed?
- ethical requirement (respect autonomy, avoid harm, promote trust)
- professional requirement
- legal requirement (avoid battery, avoid negligence
When is consent not needed?
- emergencies when it is not possible to find out the patients wishes
- if being treated under the mental health act 1983
- if a patient lacks capacity and the treatment is deemed in the patients best interest (mental capacity act 2005)
- if the public health (control of disease) act 1984 applies (allows detention of patient in hospital if they present an infectious disease risk to the public)
- to disclose confidential information in some circumstances (e.g. some one else is at risk of harm)
At what age are children presumed competent to consent?
16
When can children under 16 give consent to treatment?
If they are Gillick / Fraser competent
At what age can a competent person refuse treatment?
18
- under 18s can be given treatment against their wishes if it is deemed in their best interest and their parents or the courts consent for them
What is self-medication?
- the ability to select and use medication to treat self recognised illness or symptoms
- an element of self care
What is self care?
- an integral part of daily life
- individuals taking responsibility for their own health and wellbeing
- actions taken to stay fit, maintain good physical and mental health, meet their social and psychological needs, prevent illness or accidents, and care effectively for minor ailments and longterm conditions
What do people self-medicate with?
- pharmacy medications
- general sales list medications
- herbal medications
- homeopathy
- vitamin, mineral and food supplements
- smoking and alcohol use
- illicit drug use
What are the three categories of ways that medicines can be sold in the UK?
- prescription only medication (POM)
- without a prescription but under the supervision of a pharmacist (P)
- in general retail outlet, as a general sales list (GSL) medication
What is the Self-medicating scale? (SMS)
- a scale to measure peoples beliefs about self medication
- based on beliefs about analgesics
- three categories:
- - reluctant to take mild analgesics
- - don’t think twice about taking mild analgesics
- - prefer to let the pain run its course
What are the four types of data most commonly encountered in health research?
INTERVAL
Quantitative, two types:
- discrete (only certain values are possible) e.g. number of falls
- continuous (any value is possible) e.g. height
ORDINAL
Qualitative but ordered e.g. satisfaction scale with categories: unsatisfied, neutral, satisfied, very satisfied
NOMINAL
Qualitative, with more than two categories that are not ordered e.g. single, married, divorced, widowed
Describe a normal distribution
- bell-shaped curve
- mean=median=mode, with 50% of the data either side
- 95% of the observations lie within 1.96 standard deviations from the mean
- 68% of observations lie within one standard deviation from the mean
Describe a negative skew
- tail of the data to the left
Describe a positive skew
- tail of the data to the right
Describe the process of hypothesis testing
- state the null and alternative hypothesis
- define and evaluate a test statistic
- calculate a p-value
- interpret the results
What is a Type 1 error?
- FAR: falsely accept the research, falsely reject the null
What is a Type 2 error?
- FAN: falsely accept the null
What is confidentiality?
- the principle of not divulging information about patients to others
- sometimes qualified with “without the patient’s consent”
Why respect confidentiality?
- central to establishing trust
- ensures information is not disclosed to the wrong people
- respects patients autonomy
- a legal requirement
- a professional obligation
What is the definition of a breach of confidentiality?
- when information is shared with other people without the consent of the patient
When is a breach of confidentiality justified?
- when it is in the public interest
- to prevent serious harm coming to another person
- disclosures required by law
- when it is in the patient’s best interest and they lack capacity or are a child
What should you do if sharing patient information?
- get their express consent if identifiable information is to be disclosed for purposes other than their care or a local clinical audit (unless disclosure is required by law or is in the public interest)
- use anonymised or coded information if practical
- keep disclosures to the minimum necessary
- keep up to date with and observe all relevant legal requirements
Why is ethnicity important in medicine?
- it is a part of who we are
- it is a sensitive subject
- disease prevalence varies with ethnicity
- response to and perception of treatment may vary with ethnicity
- it affects how people, including doctors, behave towards others
What might be the consequences of eligibility for testing being based on ethnicity?
- people may be stigmatised
- gives the impression of ethnic minorities being sicker and bringing disease to the community
- potential resentment to resources being directed towards ethnic minorities
What do descriptive and analytic mean when classifying population research?
Descriptive:
- “what is it like?”
- dont need a control
- assessed at one point in time
- e.g. survey, case report, case series
Analytic:
- “why is it like this?”
- need controls
- assessed across time
- two subclasses:
- experimental e.g. trials
- observational e.g. cohort or case-control
Define risk
the probability that an event will occur during a specified time (a quantified uncertainty)
How do you calculate relative risk?
absolute risk of events in target group / absolute risk of events in control group
How do you calculate absolute risk?
number of events / number of people in the group
