1. Reliability in Testing
Is the test or assessment tool
consistent and dependable?
• Student-related reliability
• Rater reliability
• Test administration reliability
• Test reliability (Brown, 2004, 20-22)

2. Student-related reliability
• Give students consistent materials/time for
test preparation
• Plenty of time for studying
• Consistent test time/conditions (always on
Wednesdays)

3. Rater reliability
• For subjective scoring in high stakes tests:
 Have more than one rater
 Use rubric and have traning/norming sessions
 Have outside periodic oversight
 Keep tests anonymous
• For low stakes tests (quizzes):
 Use rubric
 Read through all tests before rating

4. Test administration reliability
• Consistent rules for all classes/teachers:
 Dictionary use
 Notes/books
 Strict time limits

5. How to measure test reliability?
One way is through test-retest method:
• The same group of students takes the same test
twice. (drawback- motivation and washback)
What else could we do to test whether the
same students (or very similar students)
score the same on the same test twice?

6. Split half method
Have the test split Then measure the This is a good way to
into two halves, scores for each half look at reliability, but
equal in tasks and it requires that the
difficulty. split tests are really
equal

7. Split half method – Your task
• What can you tell about the reliability for
the following split sections on my test?
Joanna 88 95
Jenny 90 87
Asuka 97 95
David 92 88
Annick 74 78
Mercedes 84 89

8. Checklist for Reliability (1)
• Have many independent items
• Delete items that do not discriminate between
weaker/stronger students
• Limit choices – restrict student responses
• Keep items clear and unambiguous
• Provide clear instructions and examples
• Keep type large enough and cleanly copied

9. Checklist for Reliability (2)
• Provide practice with testing format
• Keep administration uniform
• Have clear answers for all items (as possible)
• Provide detailed answer key
• Train raters as necessary
• Determine acceptable responses before scoring starts
• Keep test-takers anonymous
John Bunting (2004) presentation in the Course: Testing, Assessment and Teaching- A
program for EFL Teachers at UABC. Facultad de Idiomas, UABC