Types of Validity and Reliability

1. Test-Retest Estimates of Reliability

1.1. Obtained by administering the same test twice to the same group of individuals, with a small time interval between testing and correlating the scores.

2. Internal Consistency Estimates of Reliability

2.1. Falls into 2 general categories

2.1.1. Split-Half/Odd-Even

2.1.1.1. Divide a test into halves and correlate the halves with one another - obtained correlations underestimate the reliability of the whole test.

2.1.2. Item-total correlations/Kuder-Richardson (KR)

2.1.2.1. Methods determine the extent to which the entire test represents a single, fairly consistent measure of a concept.

2.2. Internal Consistency Estimates

2.2.1. Tend to yield inflated reliability estimates for speeded tests.

3. Alternate-form Estimates of reliability

3.1. Obtained by administering 2 alternate or equivalent forms of a test to the same group and correlating their scores.

4. Content Validity Evidence

4.1. Assessed by systematically comparing a test item with instructional objectives to see if they match

5. Criterion-related Validity Evidence

5.1. Established by correlating test scores with an external standard or criterion to obtain a numerical estimate of validity evidence.

5.1.1. Concurrent Validity evidence

5.1.1.1. Determined by correlating test scores with a criterion measure collected at the same time.

5.1.2. Predictive Validity evidence

5.1.2.1. Determined by correlating test scores with a criterion measure collected after a period of time.

6. Construct Validity Evidence

6.1. Determined by finding whether test results correspond with scores on other variables as predicted by some rationale or theory.