Psychology

Psychology
Introducing key terms Reliability

WJEC EDUQAS

Read the words and discuss what you think they might mean before revealing the definition.

Internal reliability — The extent to which a test or measure is consistent within itself e.g. the use of a standardised instructions and procedure for all participants.

External reliability — The extent to which a test produces consistent results over several occasions.

Ways of dealing with reliabilityA measure which improves consistency and accuracy within the results e.g. the use of a standardised procedure or measures such as counterbalancing.

Assessing reliability* — Measures used to check the consistency of a set of results.

Inter-rater reliability* — Where two or more psychologists produce consistent results by using a standardised procedure, agreed coding system, or correlation of their data.

Test-retest reliability* — Involves testing and retesting the same participants over time, with the same test, and comparing their scores. If the scores are the same the test has external reliability.

Split-half reliability* — Involves splitting a pp’s test answers in half and seeing whether s/he got the same or similar scores on the two halves. If so, internal reliability is high; if not, it is low and individual questions would need to be redesigned.

* A2 WJEC