Use of Data Flashcards
About how many people consult GPS about their complaints?
About 20%
About what percentage of the population are referred on to hospital investigation or care?
3%
Does severity of illness accurately parallel severity of disease?
No
What defines disease?
Symptoms, signs, diagnosis. Biomedical perspective.
What defines illness?
Ideas, concerns, expectations - experience.
Give an example of disease with no illness?
Hypertension
But basically anything asymptomatic!
What is the lay referral system?
This consultation with friends and family about the meaning of symptoms.
What are factors affecting the uptake of care?
- Concept of Lay Referral
- Sources of Info - Peers, family, Internet etc
- Medical factors -New symptoms, visible symptoms, increasing severity
- Non medical factors - crisis, peer pressure, expectations, class etc
What happens to contact rates in males and females with GPs with age?
Contact rates increase
What are the three main aims of epidemiology?
- Description
- Explanation (Identify aetiology)
- Disease control
Why does epidemiology compare population groups?
- Aetiological clues
- Scope for prevention
- Identification of high risk groups
What does a rate refer to in terms of epidemiology of a condition?
Events/Population at risk
What does relative risk measure?
Strength of an association between a suspected risk factor and the disease under study
How is relative risk calculated?
Incidence of disease in exposed group/incidence of disease in unexposed group
List some sources of epidemiological data?
Mortality data Hospital activity statistics Reproductive health statistics Cancer statistics Accident statistics General practice morbidity Health and household surveys Social security statistics Drug misuse databases Expenditure data from NHS
What is health literacy?
-Having the knowledge, skills, understanding and confidence to use health information, to be active partners in their care and to navigate health and social care systems.
What is the purpose of SIGN guidelines?
Help professionals and patients understand medical evidence - make decisions
Reduce unwarranted variations in practice
Improve healthcare across Scotland by focusing on patient-important outcomes
What is a descriptive study?
Attempts to describe the amount and distribution of a disease in a given population.
What is a cross-sectional study?
An analytic study where observations are made at a single point in time
(Disease frequency, survey, prevalence study)
What is a case control study?
An analytical study in which two groups of people are compared.
(People who have the illness (cases) and those who dont (controls))
What can be used as a guide as to whether a result may be a chance finding?
P values
What is a cohort study?
An analytical study in which baseline data on exposure are collected from a group of people who DO NOT have the disease.
Followed through time until sufficient number have developed the disease.
What is a trial?
An experiment used to test ideas about aetiologies/evaluate interventions?
What is the definitive method of assessing any new treatment in medicine?
Randomised control trials
What is standardisation?
A set of techniques used to remove (or adjust) the effects of difference in confounding variables.
What is a standardised mortality ratio?
The number of deaths expressed as a ratio to the number of expected deaths.
What are some factors to consider in interpreting results?
Standarisation Standarised Mortality Ratio (SMR) Quality of Data Case Definition Coding/ Classification Ascertainment (complete data?)
What defines bias?
Any trend in the collection, analysis, interpretation, publication or review of data that can lead to conclusions systemically different from the truth
List some types of bias
Selection bias
Information bias
Follow up bias
Systematic Error
What is selection bias?
Certain groups being deliberately allocated to one branch of a trial
What is information bias?
Arises from errors in measuring exposure or disease - the researcher influencing the study based on knowledge.
(Ie when the study isn’t double-blinded)
What is follow up bias?
When one group of subjects is followed up more assiduously than another.
What is systematic error?
Where there is a tendency for measurements to always fall on one side of the true value.
May be due to the instrument or person.
What is a confounding factor?
One that is independently linked to both the risk factor and disease being investigated - and so distorts the relationship.
List some criteria for causality
Strength of association Consistency Specificity Temporality Biological gradient Biological plausibility Coherence Analogy Experiment
What is the only absolute criterion for causality?
Temporality
