ppt Establishing the Validity and Reliability of a Research Instrument

1. Establishing the Validity and
Reliability of a Research
Instrument
JENNELYN S. MALTIZO
Discussant

2. What is validity?
Validity is about the accuracy of a
measure.

3. What is reliability?
Reliability is about the consistency
of a measure.

4. Types of Validity

5. 1. Construct Validity
the adherence of a measure to
existing theory and knowledge of the
concept being measured.

6. 2. Content Validity
- the extent to which the
measurement covers all aspects of the
concept being measured.

7. 3. Criterion Validity
- the extent to which the result of a
measure corresponds to other valid
measures of the same concept.

8. The Concept of Reliability

9. 1. Test-Retest Reliability
- the consistency of a measure across
time.

10. 2. Inter-Rater Reliability
- the consistency of a measure across
raters or observers.

11. 3. Internal Consistency Reliability
- the consistency of the
measurement itself.

12. 4. Parallel Forms Reliability
- it is a measure of reliability used in
psychometrics to assess the consistency of
test scores across different versions, or forms,
of a test that are designed to measure the
same construct.

13. 5. Split-half Reliability
- it is a measure of internal consistency
reliability used in psychometrics to assess
the reliability of a test.

14. Threats to Validity

15. 1. Selection Bias
- occurs when participants selected for the
study are not representative of the population
being studied.

16. 2. Maturation
- refers to changes in participants over
time that affect the outcome of the study,
independent of the treatment or
intervention.

17. 3. History
- external events or experiences that
occur during the study and affect
participants’ responses, confounding
the results.

18. 4. Testing Effects
- occur when participants’ responses
are influenced by having taken the test
previously.

19. 5. Instrumentation
- changes in the measurement
instrument or procedures over the
course of the study that affect the
results.

20. 6. Regression Toward the Mean
- refers to the tendency for extreme
scores on a variable to move closer to
the mean upon retesting.

21. 7. Experimental Mortality
- occurs when participants drop out of
the study before it is completed,
potentially biasing the results.

22. Threats to Reliability

23. 1. Measurement Error
- random errors or inconsistencies in
measurement that can occur due to
various factors such as human error,
instrument malfunction, or ambiguous
wording of items.

24. 2. Inter-Rater Variability
- differences in ratings or judgments
between different observers or raters.

25. 3. Test-Retest Variability
- changes in participants’ responses
upon retesting, which may not reflect
true changes in the construct being
measured.

26. 4. Sampling Variability
- variability in results due to difference
in the composition of samples or
participants across different
administrations of the test.

27. 5. Order Effects
- occur when the order in which items
are presented influences participants’
responses.

28. 6. Response Bias
- systematic tendencies for participants
to respond in a certain way, regardless
of the content of the items.

29. 7. Instrumentation Changes
- changes in the measurement
instrument or procedures over time
that affect the consistency of
measurement.

30. ThankYouforListening!