Knowledge check

Knowledge check: Psychometrics: reliability, validity and screening accuracy

Linked to the module Psychometrics: reliability, validity and screening accuracy. Study the module first, then test yourself.

1 A depression scale gives very different scores when the same stable person completes it twice in a week. Which property is weak?

Multiple choice Introductory

Test–retest reliability Content validity Specificity Face validity

Basis: Textbook concept, original question

2 A test can be highly reliable but still invalid for a particular purpose.

True / false Introductory

True False

Basis: Textbook concept, original question

3 Sensitivity is the proportion of:

Multiple choice Intermediate

People without the condition who screen negative People with the condition who screen positive Positive screens who have the condition All people who screen positive

Basis: Textbook concept, original question

4 Why does the positive predictive value of a screen fall when a condition becomes rarer?

Multiple choice Advanced

Sensitivity always falls False positives make up a larger share of positive results The test becomes less reliable Specificity always rises

Basis: Textbook concept, original question

5 What is the most appropriate response to a positive result on a depression screen?

Multiple choice Introductory

Record a diagnosis of depression Arrange a fuller clinical assessment Ignore it because screens are inaccurate Start medication

Basis: Textbook concept, original question