Clinical trials

Question 1

what are the aims of a scientific study

Answer 1

1. seeks to establish facts
2. contributes to knowledge
3. confirms, adds or establishes theory
4. should be controlled so free of bias
5. should be designed on a scale that the results can be statistically evaluated

Question 2

what does the scientific method involve

Answer 2

1. hypotheses
2. procedures- experiments
3. data- results
4. findings- conclusions

Question 3

what do detailed scientific studies require

Answer 3

1. expensive to conduct
2. require specialised skilled operators to
   - design
   - analyse
   - interpret the data

Question 4

what is epidemiology

Answer 4

1. study of how often diseases occur in different groups of people and why
2. used to plan and evaluate strategies to prevent illness and as a guide to the management of patients

Question 5

what are the types of clinical studies

Answer 5

1. qualitative research- focus groups, individual interviews
2. observational studies- case studies, cohort studies, cross sectional studies
3. experimental studies- clinical trials

Question 6

what is involved in qualitative research

Answer 6

1. collecting and analysing non numerical data
2. understanding concepts, opinions and experiences
3. gather in depth insight into problems
4. generate new ideas for research

Question 7

what do observational studies involve

Answer 7

1. researchers observe the effect of something on a population
   - disease
   - risk factor
   - diagnostic test
   - treatment or intervention
2. is not experimental- doesn’t try to change who is or isn’t affected

Question 8

what are cross sectional studies

Answer 8

measure the frequency of a disease or condition in a defined population at a given time
- a census of occurrence of characteristics

Question 9

what are case studies

Answer 9

1. medical history of one (or small group of) patients
2. no control group

Question 10

what is a case control study

Answer 10

1. compares patients who have a condition with a group who do not have that condition
2. looks retrospectively at risk factors that may impact on the condition

Question 11

what are the advantages and disadvantages of case control studies

Answer 11

1. good for studying rare conditions
2. relatively quick to set up- as they are retrospective
3. can look at multiple risk factors
4. clinical records may be inconsistent
5. may rely on memory- recall bias

Question 12

what are cohort studies

Answer 12

1. observational studies of subjects with a specific disease or characteristic
2. may be compared to a control group
3. usually over a long time period

Question 13

give an example of a retrospective study

Answer 13

case control studies

Question 14

give an example of a present study

Answer 14

cross sectional snapshot

Question 15

give an example of a prospective study

Answer 15

prospective cohort study

Question 16

what are experimental studies

Answer 16

1. introduce an intervention
2. study the effects on the treated population

Question 17

what is involved in clinical trials

Answer 17

1. specified condition and specified treatment
2. test and control group
3. measure the outcomes

Question 18

what are randomised controlled trials

Answer 18

1. population of patients chosen
2. divided into 2 groups
3. trial group compared with control group

Question 19

what is a meta analysis of randomised controlled trials

Answer 19

1. a type of systematic review that focuses on the numerical results
2. aim is to combine the results to produce an estimate of the overall effect size
3. data from several trials are pooled and averaged to estimate the overall effect
4. no new raw data collected

Question 20

outline the hierarchy of evidence starting from the bottom of the hierarchy to the top

Answer 20

1. case series/reports
2. case control studies
3. cohort studies
4. randomised control trials
5. systematic review/meta analysis