Study Design Sampling And Recruitment

Question 1

Definition of sample

Answer 1

A small part of something that is intended to represent the whole thing

Question 2

Definition of population

Answer 2

All persons that have similar characteristics = census

Question 3

Definition of sampling

Answer 3

The process of selecting a sample from the population to be studied

Question 4

Definition of external validity

Answer 4

Consider how representative the study participants are of the disease, disability, people, phenomenon in the population

Question 5

Definition of internal validity

Answer 5

How to chose study participants in order to ensure that the study ca n answer the research aquestionquestion

Question 6

What are the different probability sampling methods ?

Answer 6

• simple random sampling
• stratified random sampling
• systematic random sampling
• clustered random sampling

Question 7

What is probability sampling ?

Answer 7

All persons in the target population have equal chance of being selected

Question 8

Define simple random sampling

Answer 8

The whole population is available for selection

Question 9

What is stratified random sampling

Answer 9

The whole population is available for selection but sample is selected from sub-groups

Question 10

What is systematic random sampling

Answer 10

Selection at defined intervals

Question 11

What is clustered random sampling

Answer 11

For very large population which requires subdivisions into geographical areas

Question 12

Define non-probability sampling

Answer 12

Selection process does not guarantee equal chances of selection for all entities in the target population

Question 13

What is convenience sampling ?

Answer 13

Used in qualitative research and case series research, selection is based on availability

Question 14

What is purposive sampling ?

Answer 14

Must be used in qualitative research, selection is based on the subjective judgment of the researcher that a potential participant can be an expert. May be combined with random sampling for large populations.

Question 15

What is Snowball sampling ?

Answer 15

When the population is uneasy to access, researcher requests access to colleagues, friends, relatives of a known research participant. It can be used in any type of research (qualitative, quantitative)

Question 16

What is the goal of PIO question

Answer 16

Report an observation or to associate the effects of intervention with the outcome

Question 17

What is the goal of PICO question ?

Answer 17

To establish a causal relationship between the intervention and the outcome

Question 18

What is the goal of qualitative question ?

Answer 18

Observe and describe phenomena. It is also used to describe how people cope with this phenomena.

Question 19

What are the components of qualitative question ?

Answer 19

• a population
• a phenomenon of interest
• the connection between population and phenomenon of interest

Question 20

What is delimitation ?

Answer 20

To narrow the focus of your enquiry to a manageable number of items or factors. It means that you identify the potential weakness in the study but also define exclusion and inclusion criteria, determine the research instruments and procedures.

Question 21

What study design is linked to the word “EFFECTIVE”

Answer 21

RCT

Question 22

What is prevalence ?

Answer 22

It’s the proportion of the population that has a condition at a specified point in time

Question 23

What is incidence ?

Answer 23

It’s the number of new cases of a condition during a specific period of time

Question 24

What study design is linked to words “HOW MUCH EACH (YEAR)”

Answer 24

Cross sectional study

Question 25

Which sampling method can you use for a cross sectional study were disease register doesn’t exist ?

Answer 25

Clustered random sampling

Question 26

What type of study design is linked to the word “COPE”

Answer 26

Qualitative study with purposive sampling

Question 27

Definition of recruitment

Answer 27

The process of getting the right people to agree to participate in your study

Question 28

What are the recruitment methods ?

Answer 28

• Cold call
• Advertisements
• Direct recruitment
• Snowball sampling

Question 29

Define cold call

Answer 29

How to : Letter email phone call to people who have never heard about the study

Resources and requirements : public/private records to identify potential participants

Question 30

Define Advertisement

Answer 30

How to : place adverts in newspapers, internet, television, magazines. Print out posters and flyers and pin them in public places.

Resources and requirements : the target population must regularly access the medium of advertisement

Question 31

Define direct recruitment

Answer 31

How to : invite patients directly from clinics and hospitals

Resources and requirements : the researcher collaborates with healthcare professionals. The healthcare professionals recruit research participants on behalf of the researcher (the healthcare professional may also be the researcher).

Question 32

How to snow ball sampling ?

Answer 32

How to : ask current participants to refer their friends and relatives to you

Question 33

How to get valid consent from people who do not have the capacity to consent

Answer 33

Does this potential participant have an advance notice. If not, the caregiver may get consent from the primary carer.

Question 34

What is advanced directive ?

Answer 34

Is a legal document prepared by a person to specify how they wish to engage with healthcare services and society at large if they ever loose their capacity to consent

Question 35

What are the actions of the researcher to ensure ethical principles ?

Answer 35

1) give information to the potential participant
- terms of participation
- how the research will benefit the participant and society
- what are the compensation/ incentives
- right to confidentiality and privacy
- right to withdraw consent at any time

2) Check the capacity to consent
- the ability of the potential participant to use the above mentioned informations provided to make informed decision

3) Give time between information and consent
4) signing the informed consent

Question 36

Does the cold call violate the ethical principles ?

Answer 36

They don’t if they are used in non invasive types of investigation, ex: qualitative surveys