Trials And Evidence

Question 1

What is single blinding?

Answer 1

Where the study participant does not know whether they are in the placebo or trial group

Question 2

What is double blinding?

Answer 2

Where the study participants and investigator does not know about study participants allocation either trial or control group

Question 3

What is triple blinding?

Answer 3

Where the study participants, investigator and statician do not know about the study participants allocation to either control or trial group

Question 4

What is intention to treat analysis?

Answer 4

All the patients who were enrolled and randomly allocated to treatment are included in the analysis of a study even if some patients dropped out of the study

Question 5

What is meta-analysis?

Answer 5

A statistical procedure for combining data from multiple studies

Question 6

What is a case series?

Answer 6

A study that samples patients with specific outcome or specific exposure

Question 7

What is a randomised control trial?

Answer 7

A trial where subjects are allocated randomly into an intervention or control group

Question 8

What is a cohort study?

Answer 8

A study where one or more samples (cohorts) are followed prospectively and subsequent evaluations sign respect go disease or outcome are conducted to determine which initial participants exposure characteristics are associated with the disease or outcome

Question 9

What is a case control study?

Answer 9

An observational study where two existing groups differing in some outcome are identified and compared on the basis of some supposed causal attribite

Question 10

What is a cross sectional study?

Answer 10

A type of observational study that analyses data from a population at a specific point in time

Question 11

What is internal validity?

Answer 11

Experimental design is structured and encompasses all of the steps of the scientific research method

Question 12

What is external validity?

Answer 12

The process of examining the results and questioning whether there are any other possible causal relationships

Question 13

What is selection bias?

Answer 13

Systematic differences in the comparison groups attributable to incomplete randomisation

Question 14

What is performance bias?

Answer 14

Systematic differences in the care provided, apart from the intervention being evaluated

Question 15

What is exclusion bias?

Answer 15

Systematic differences in withdrawals from the trial

Question 16

What is detection bias?

Answer 16

Systematic differences in outcome assessment

Question 17

What is p value?

Answer 17

The probability that an outcome would have arisen by chance

Question 18

What is number needed to treat?

Answer 18

The average number of patients who need to receive treatment or other intervention for one of them to get the positive outcome in the time specified

Question 19

The higher the number needed to treat the less effective the treatment. T/F?

Answer 19

True

Question 20

What is the order of different types of studies in the hierarchy of evidence from weakest to strongest?

Answer 20

Case series
Cross sectional study
Case control studies
Cohort study
Randomised control trial
Meta analysis
Systematic review

Question 21

What is the aim of qualitative research?

Answer 21

To understand what it is like for the patient to live with a condition
To understand how patients feel and what they think about their care and treatment

Question 22

Describe the use of observational studies

Answer 22

Used to collect information about patients without trying to influence their exposure to a treatment or intervention that may prevent disease
Used when experimentation intervention is unethical to implement or when it is not appropriate to generalise

Question 23

What is the protocol for setting up a randomised control trial?

Answer 23

Research question formulated
Selection criteria made
Eligibility criteria made
Estimate sample size
Randomise patients
Intervention carrried out
Robust statistical analysis
Monitoring and management of clinical tiral

Question 24

How do patients act as their own control in cross over trials?

Answer 24

In these trials patients eventually get all of the different treatments, they just receive them in different orders in order to maintain blinding and to prevent bias

Question 25

What does monitoring snd management of clinical trials involve?

Answer 25

Quality assurance and participant management
Data monitoring, evaluation and reporting
Trial committees
Regular follow up

Question 26

What is the placebo effect?

Answer 26

A beneficial effect produced by a placebo drug or treatment which cannot be attributed to the properties of the placebo itself where the patient perceives an improvement in symptoms from the psychological effect of receiving treatment

Question 27

What is a confidence interval?

Answer 27

A range of values that has a specified probability of containing the true population parameter being investigated

Question 28

What is number needed to harm?

Answer 28

A measure of the chance of experiencing a specified harm in a specified time because of the treatment or other intervention

Question 29

What is the difference between superiority, equivalence and non inferiority trials?

Answer 29

Superiority trials aims to show that a new intervention is better than the comparison
Equivalence trials aim to show that two interventions have the same clinical benefit
An non inferiority trial aims to show that the effect of a new treatment cannot be said to be significantly weaker than that of a current treatment

Question 30

What are some of the disadvantages of a randomised control trial?

Answer 30

Costly and time consuming
Participants may not be a representative sample of the population
Recruitment may be difficult and small RCTs may lead to false conclusions
Administrative complexity of trial

Question 31

What is a positive control?

Answer 31

A sample that should definitely give a positive result and so can test experimental design

Question 32

What is a negative control?

Answer 32

A sample that should definitely not give a positive result and so can be used to test experimental design