Y2 Use of Data

Question 1

What percentage of patients are referred to secondary care by GPs?

Answer 1

3%

Question 2

What percentage of patients actually go to GP with complaint?

Answer 2

30%

Question 3

Definition of disease

Answer 3

Symptoms and signs allow diagnosis. Biomedical perspective of condition

Question 4

Definition of illness

Answer 4

Ideas, concerns and expectations. Experience of the condition (patient’s perspective)

Question 5

Factors affecting uptake of care

Answer 5

> Concept of lay referral
Sources of information such as TV, peers, magazines, internet, adverts in public places, newspapers
Medical factors - new symptoms, visible symptoms, increasing severity, duration of symptoms
Non-medical - crisis, peer pressure, patient beliefs, expectations, social class, economic factors, psychological, environment, cultural, ethnicity, age, gender, media

Question 6

Aims of epidemiology

Answer 6

> Description - to describe amount and distribution of disease in human populations
Explanation - to elucidate the natural history and identify aetiological factors for disease usually by combining epidemiological data with data from other disciplines
Disease control - provide basis on which preventative measures, public health practices and therapeutic strategies can be developed, implemented, monitored and evaluated for the purposes of disease control

Question 7

How is relative risk calculated and what does it show?

Answer 7

> RR = Incidence of disease in exposed group / incidence of disease in unexposed group
Measure of strength of an association between suspected risk factor and the disease under study

Question 8

Sources of epidemiological data

Answer 8

> NHS expenditure date
> Cancer statistics
> Accident statistics
> Hospital activity statistics
> Mortality data
> GP morbidity
> Health and household surveys
> Social security statistics
> Drug misuse databases

Question 9

What is health literacy?

Answer 9

It is about people having the knowledge, skills, understanding and confidence to use health information, to be partners in their care and to navigate health and social care systems

Question 10

What is the CHA2DS2-VASc score?

Answer 10

Used for estimating risk of stroke in patients with non-rheumatic AF

Question 11

What are the SIGN guidelines intended to do?

Answer 11

> Help health and social care professionals and patients understand medical evidence and use it to make decisions about healthcare
Reduce unwarranted variations in practice and make sure patients get the best care available, no matter where they live
Improve healthcare across Scotland by focussing on patient-important outcomes

Question 12

What are the two main types of study?

Answer 12

Descriptive

Analytical

Question 13

Explain more about descriptive studies

Answer 13

> They describe the amount and distribution of a disease in a given population
May give possible clues to risk factors and aetiologies
Useful for detecting emerging health problems

Question 14

What are the different types of analytical studies and a bit about them?

Answer 14

> Cross sectional - observations are made at a single point in time, used to draw conclusions about relationship between disease and variables in a population
Case-control study - group of individuals with a disease are compared with a group who don’t, looks at risk factors and precious exposures to compare, expressed as relative risk or odds ratio
Cohort studies - baseline data is collected from a group who don’t have a disease then they are followed until a sufficient number of them have developed the disease to allow analysis

Question 15

What is the definitive method of assessing any new treatment in medicine?

Answer 15

Randomised controlled trial

Question 16

What factors need to be considered when interpreting the results of a trial?

Answer 16

> Standardisation (set of techniques used to remove effects of differences due to confounding variables)
Standardised mortality ratio (special type of standardisation which allows death rate of a population to be expressed as a proportion of the standard reference population death rate e.g. if Grampian’s SMR is 120 (Scotland’s being 100), 20% more deaths have occurred in Grampian than the national average)
Quality of data
Case definition (what is classed as having the disease and what is not)
Coding and classification (under what heading should the data be filed under)
Ascertainment (is the data complete?)

Question 17

What are the 4 types of bias?

Answer 17

> Selection (where a sample group is not representative of the whole study population)
Information (arises from systematic errors in measuring exposure or disease, researcher may be asking more questions if the person is in the case group to get more information)
Follow-up (one group is followed-up more than the other to measure disease incidence)
Systematic error (form of measurement bias where there is tendency for measurements to fall one side of the true value, e.g. faulty equipment)

Question 18

What is a confounding factor?

Answer 18

A factor which is associated independently with both the disease and the exposure under study so distorts the relationship between the two. Accounted for by randomisation, selective eligibility and adjusting the results

Question 19

What are the criteria for causality?

Answer 19

> Strength of association
> Consistency
> Specificity
> Temporality (only absolute criterion)
> Biological gradient
> Coherence
> Analogy
> Experiment