Week 1: Decisions and Evidence Flashcards
Define Diagnosis
The process of determining the nature of a disorder by considering the patient’s signs and symptoms, medical background, and – when necessary – results of laboratory tests and X-ray examinations.
Unlike therapeutic procedures, diagnostic processes usually do not directly benefit the patient in terms of treatment.”
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
Define Treatment decision
Decisions can be defined as
“a choice of action – of what to do or not to do.” (Baron, 1994, p.4)
If applied to medicine – a choice of what action (if any) to take to treat a patient.
What are the 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?
Focus on more descriptive approaches
Look at how decisions are made in practice
Often compared to normative models (highlight areas where ‘errors’ are made)
What is Diagnostic (Clinical) Reasoning?
Most common area of research in medical decision making
Focus on how doctors make diagnoses
Research has often compared ‘expert’ clinicians with more junior or novice clinicians
And how experts become experts…i.e. what is the process of becoming an expert? What changes?
Hypothetico-deductive model
seeking evidence to disprove your hypothesis
(Elstein et al, 1978)
Cue Acquisition….
Hypothesis Formation….
Cue Interpretation….
Hypothesis Evaluation….(& start over again if necessary)
What is prospect theory (Tversky & Kahneman, 1988) ( decision making)?
Suggests there are two phases in the choice process
1) Framing and editing. The preliminary analysis of the decision problem.
2) Phase of evaluation. Framed prospects evaluated and prospect with highest value selected.
What is a decision process influenced by?
Framing: how the problem is framed (NB possible role of bias).
Values: people’s values or beliefs associated with benefits and harms of different options and outcomes.
Evaluation: people’s ability to evaluate the information used.
Define Evidence?
Narrow definition• Results of rigorous clinical trials and observational studies i.e. results from research studies•
•In Evidence-based Decision Making, generally use the narrow definition
How do you know how good evidence is?
- Matching of type of research study to the type of issue you want to address
- ‘Hierarchy of evidence’ – lists type of study design ranked in order of their perceived ability to provide evidence for use in practice (quality associated with level of potential for ‘bias’ in a study).
Evidence Pyramid
limitations of evidence pyramid
- Study designs are suited to different questions
- There are good and bad studies of any type
- The pyramid doesn’t include qualitative research (ie research gathering words, not numerical data)
- Be cautious about using the hierarchy uncritically
5S Levels of organisation of evidence (adapted from Haynes 2006)
•What sort of evidence might be used in a clinical situation?
•Statistics?•Knowledge and experience?•Research?
