Tutorial 1

Question 1

what is epidemiology?

Answer 1

study of nature and type of illness in a society using numerical science

Question 2

what is the ratio of determining epidemiology?

Answer 2

number of events/ population at risk

Question 3

what can epidemiological data be used for?

Answer 3

assist making diagnosis
ensure high quality services
assess decisions in which services are required for prevention and diagnosis

Question 4

what can epidemiology be used to detect or determine?

Answer 4

can determine aetiological clues
scope of prevention of a disease
identify high risk groups

Question 5

state some sources of epidemiological data?

Answer 5

mortality data
NHS expenditure 
household surveys 
hospital activity data
social security data 
disease registers 
cancer statistics

Question 6

what are the three aims of epidemiology?

Answer 6

description - incidence, prevalence
explantation - relative risk, actual risk
disease control - advice on treatments and prevention

Question 7

what is incidence ?

Answer 7

number of new cases of a disease at one point in time

Question 8

what is prevalence ?

Answer 8

number of people with a disease over a period of time

Question 9

what disease has high incidence but low prevalence?

Answer 9

motor neuron disease

Question 10

what disease has low incidence and low prevalence?

Answer 10

ebola

Question 11

what influences prevalence?

Answer 11

cure of disease or death

Question 12

what is relative risk?

Answer 12

the strength of association between a risk factor and a disease

Question 13

what is actual risk?

Answer 13

the probability of disease as a result of a specific risk factor

Question 14

what is the ratio used for relative risk?

Answer 14

disease in exposed group/ disease in unexposed group

Question 15

state some types of studies?

Answer 15

descriptive studies 
cross sectional studies 
case control study
cohort study 
randomised control trial

Question 16

what is a descriptive study?

Answer 16

description of amount and distribution of disease in a population at one point in time
- follow the TIME, PLACE, PERSON framework

Question 17

what are some benefits of descriptive studies?

Answer 17

cheap, quick, easy
generates hypothesis of aetiology
assesses need for health services
identifies emerging public health problems

Question 18

what is a prospective study?

Answer 18

looking forward in time

- cohort study

Question 19

what is a retrospective study?

Answer 19

looking back in time

- case control study

Question 20

what is a cross sectional study?

Answer 20

observations made at one point in time

Question 21

describe a case control study?

Answer 21

two groups of people are studied, one group with the disease in question and the other group free of the disease in question.
studying the risk factor exposure in each of the two groups can provide information on what factors increase risk of disease

Question 22

what is a cohort study?

Answer 22

a group of disease free individuals are followed up over time to determine if exposure to a risk factor influences the risk of disease
after a significant amount of time when sufficient number of people have developed the disease in question the exposure to risk factors are analysed

Question 23

what study is used to determine relative risk?

Answer 23

case control studies

Question 24

out of case control and cohort studies which one is more powerful?

Answer 24

cohort

Question 25

what is a randomised control trial?

Answer 25

used in the trial of a new medication a study group is given the new medication and the control group are given the standard treatment to determine if the new medication reduces the incidence of disease

Question 26

what are some disadvantages of randomised control trials?

Answer 26

``` costly selection bias can't address all research questions limited by people giving consent may lead to false negative conclusions ```

Question 27

what is the gold standard RCT type?

Answer 27

double blind RCT

Question 28

what interpreting results what are some factors to be considered?

Answer 28

``` standardisation standardised mortality ratio case definition quality of data coding and classification ascertainment ```

Question 29

what is standardisation?

Answer 29

remove effects of differences in age and other variables when comparing two or more populations

Question 30

what is standardised mortality ratio? (SMR)

Answer 30

standardised death rate is converted into a ratio for easy comparison

Question 31

what does a SMR of 120 mean?

Answer 31

20% more deaths

Question 32

what does SMR of 80 mean?

Answer 32

20% less deaths

Question 33

what problems could arise with the case definition?

Answer 33

different doctors not meaning the same thing regarding medical terms

Question 34

what is ascertainment ?

Answer 34

important to consider the data is complete

Question 35

what are the different types of bias?

Answer 35

information selective systematic follow up

Question 36

what is information bias?

Answer 36

errors when collecting data

Question 37

what is selection bias?

Answer 37

the people chosen for the study may not accurately represent the whole study population

Question 38

what is follow up bias?

Answer 38

when more effort is made to follow up certain people in the study and some people aren't followed up

Question 39

what is systematic bias?

Answer 39

when there is a tendency for measurements to fall on one side of the true value

Question 40

what is a confounding factor?

Answer 40

a factor which independently influences the risk factor and the disease in question so influences the relationship between the risk factor and disease in question

Question 41

state some common confounding factors?

Answer 41

age social class smoking sex

Question 42

state some ways to deal with confounding factors?

Answer 42

randomisation of trials restriction of eligible criteria group people with similar confounding factors together results can be adjusted to take into account the confounding factor

Question 43

what is criteria for causality ?

Answer 43

the difficulty proving the causation of a risk factor and disease

Question 44

what is the criteria for causality ?

Answer 44

``` strength of association consistency specificity temporality biological gradient biological plausibility coherence analogy experiment ```

Question 45

what is the absolute criterion for causality ?

Answer 45

temporality

Question 46

what is temporality ?

Answer 46

the risk factors came before the disease

Question 47

what is strength of association measured in ?

Answer 47

relative risk, odds ratio (ad/cb)

Question 48

what is consistency ?

Answer 48

repeated observation in different populations

Question 49

what is biological gradient?

Answer 49

as exposure increases the risk of disease increases

Question 50

what is biological plausibility?

Answer 50

the association agrees with the disease biology

Question 51

what is coherence?

Answer 51

the association doesn't not conflict with the disease biology

Question 52

what is analogy?

Answer 52

another exposure-disease relationship exists which can act as a model for this one

Question 53

what is an audit?

Answer 53

quality improvement process that seeks to improve patient care and outcomes

Question 54

what are the steps of preforming an audit?

Answer 54

1. identify problem 2. set criterion and standards 3. data collection - avoiding bias 4. compare data with criterion and standards 5. implement changes 6. re audit

Question 55

what are the steps of performing a case control study?

Answer 55

1. define case definition 2. determine how many case and controls are required 3. identify cases (same population with the disease) 4. identify control (should be from the same population) 5. decide on exposure data to be collected 6. collect data (avoiding bias) 7. analysis the data using standardised techniques

Question 56

what % of adverse events lead to disability or death?

Answer 56

33%

Question 57

what does SIGN stand for?

Answer 57

scottish intercollegiate guidelines network

Question 58

what are the stages of the Gibbs cycle?

Answer 58

``` description feelings evaluation analysis conclusion action plan ```