Reliabilty

Question 1

What is reliability?

Answer 1

Refers to how consistent the findings from an investigation or measuring device are. A measuring device is said to be reliable if it produces consistent results every time it is used.

Question 2

What are the two ways of assessing reliability?

Answer 2

Test-retest and inter-observer reliability

Question 3

What is test-retest reliability?

Answer 3

A method of assessing the reliability of a questionnaire or psychological test by assessing the same person on two separate occasions. This shows to what extent the test (or other measure) produces the same answers i.e. consistent or reliable.
There must be sufficient time between test and retest to ensure answers can’t be recalled, but not too long that attitudes might have changed

Question 4

What is inter-observer reliability?

Answer 4

The extent to which there is agreement between two or more observers involved in observations of a behaviour. This is measured by correlating the observations of two or more observers.

Question 5

What is the general rule for the data having high inter-observer reliability?

Answer 5

(Total number of agreements) / (total number of observations) > .80

Question 6

How can you improve reliability in questionnaires?

Answer 6

Test-retest method
A questionnaire that produces low test-retest reliability may require some of the items to be taken out or re-written, e.g replacing ambiguous open question with fixed choice alternatives

Question 7

How can you improve reliability in interviews?

Answer 7

Same interviewer each time, or interviewers must be properly trained so that one is not asking questions that are too leading or ambiguous.
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