validity
What does an instrument really measure? The validity of
a measure concerns what the test measures and how
well it does so.
There are three types of test validation procedures:
Content-description procedures, Construct- identification
procedures and Criterion- prediction procedures.
CONTENT
Face Validity
Does not refer to what the test measures, but rather
what it appears to measure
Essentially, does it appear to measure what it sets out
to measure
Based on expert judgement
Content Validity
Involves determining whether the content of a
measure adequately represents the domain of
interest, ie. does the content of the test fully cover the
important areas being assessed
Implies that the items making up the test should be
representative of the characteristics/property/trait that
is being measured
Panel experts used to evaluate the items
, CONSTRUCT
Construct validity of a measure is the extent to which
it measures the theoretical construct or trait that it is
supposed to measure
Examples of constructs are: intelligence, verbal
ability, spatial perception, eye-hand coordination...
In order to demonstrate construct validity evidence
that the test measures what it purports to measure
as well as evidence that the test does not measure
irrelevant attributes are both required
CRITERION
Concurrent
Involves the accuracy with which a measure can
identify and diagnose the current behaviour
regarding specific skills or characteristics of an
individual
Predictive
Involves the accuracy with which a measure can
predict the future behaviour of an individual
Any psychological measure can be a possible predictor. A
criterion is a benchmark variable against which scores on
a psychological measure are compared.
What does an instrument really measure? The validity of
a measure concerns what the test measures and how
well it does so.
There are three types of test validation procedures:
Content-description procedures, Construct- identification
procedures and Criterion- prediction procedures.
CONTENT
Face Validity
Does not refer to what the test measures, but rather
what it appears to measure
Essentially, does it appear to measure what it sets out
to measure
Based on expert judgement
Content Validity
Involves determining whether the content of a
measure adequately represents the domain of
interest, ie. does the content of the test fully cover the
important areas being assessed
Implies that the items making up the test should be
representative of the characteristics/property/trait that
is being measured
Panel experts used to evaluate the items
, CONSTRUCT
Construct validity of a measure is the extent to which
it measures the theoretical construct or trait that it is
supposed to measure
Examples of constructs are: intelligence, verbal
ability, spatial perception, eye-hand coordination...
In order to demonstrate construct validity evidence
that the test measures what it purports to measure
as well as evidence that the test does not measure
irrelevant attributes are both required
CRITERION
Concurrent
Involves the accuracy with which a measure can
identify and diagnose the current behaviour
regarding specific skills or characteristics of an
individual
Predictive
Involves the accuracy with which a measure can
predict the future behaviour of an individual
Any psychological measure can be a possible predictor. A
criterion is a benchmark variable against which scores on
a psychological measure are compared.
