Case Study / Case Series

Question 1

Why is case study interesting ?

Answer 1

This method of research allows :

• comparison of the effects of different conditions on one person
• tracking of range of other factors that may or may not contribute to a change in the outcome
• much more detailed description of an intervention than it is possible in a RCT
• much more control of how the intervention is delivered than in RCT

Question 2

Describe the general protocol for case series

Answer 2

• Define the objectives of the study
• define the patients, all known factors related to their condition
• define the diagnostic criteria
• define the unit of measurement of the objectives

Question 3

What is the control period

Answer 3

Period before intervention. During this period the assessment will indicate the baseline parameters of the participants. The assessment will also indicate if any other events or factors are affecting the parameters

Question 4

What is the washout period ?

Answer 4

The period during which the effects of the intervention are eliminated from the physiological systems of the participants.

Question 5

What is the follow up period ?

Answer 5

Period during which the researcher assesses how long the effects of the intervention are carried over and maintained

Question 6

What is the difference between case study and case series ?

Answer 6

Case study = 1 participant
Case series = more than one

Comparison of cases can only be descriptive ! The confounding factors are not monitored.

Question 7

what are the advantages of Case study/ series ?

Answer 7

• useful to study rare phenomena
• real life situation (but no control over the confounding factors)
• flexibility of the time frame
• outcome can generate hypothesis which will be tested in other study forms such as RCT

Question 8

What are the disadvantages of case study / series

Answer 8

• not generalizable, lack of external validity
• time consuming
• difficult to summarize as many factors can interfere in real life situation
• only descriptive : cannot establish relations between variables

Question 9

Define confounding

Answer 9

Confounding occurs when there is at least 1 other variable, the confounding factor, that has an association or causal relationship with the dependent variable