Reliability of NNAT2
Reliability is the degree to which an assessment tool produces stable and consistent results.
Types of Reliability
- Test-retest reliability is a measure of reliability obtained by administering the same test twice over a period of time to a group of individuals to evaluate the test for stability over time.
- Parallel forms reliability is a measure of reliability obtained by administering different versions of an assessment tool to the same group of individuals to evaluate the consistency of results across alternate versions.
3. Inter-rater reliability is a measure of reliability used to assess the degree to which different judges or raters agree in their assessment decisions.
4. Internal consistency reliability is a measure of reliability used to evaluate the degree to which different test items that search the same construct produce similar results.
NNAT 2 reliability
NNAT2 has been proven to be reliable
Internal consistency .95; Test-retest .85
Sample: 89,600
Sample is reflective of cross-section of U.S. population in geographic region, socioeconomic status, urban & suburban, ethnicity, and school type
Reliability scores at levels A-G range from 0.82-0.87