Give an example of test retest reliability?

A common example of test-retest reliability is when a group of participants takes the same test on two separate occasions, with a certain amount of time passing between the two administrations. If the scores obtained by the participants on the two occasions are highly correlated, it indicates that the test has good test-retest reliability. For example, if a group of students takes a math test and then takes the same test again a week later, and their scores are very similar on both occasions, it suggests that the test is reliable and consistent.

Example of Test-Retest Reliability:

Measurement: Cognitive performance

Test: Cambridge Cognitive Examination (CAMCOG)

Participants: 100 healthy adults over the age of 65

Procedure:

1. Participants took the CAMCOG test twice, with a 2-week interval between administrations.
2. The CAMCOG test scores were recorded for both administrations.

Results:

The correlation coefficient between the test and retest scores was 0.85 (p < 0.01). This high correlation indicates that the CAMCOG test is highly reliable over time, as participants obtained similar scores on both administrations.

Interpretation:

The test-retest reliability of the CAMCOG test demonstrates that it is a consistent and dependable measure of cognitive performance. It can be used with confidence to assess cognitive functioning in older adults over time, such as for tracking changes related to aging or disease progression.