Students take two different forms of the same survey that target the same construct but use different items, and their scores on each form are recorded. The scores from the two forms are then correlated, with higher correlations between 0.8 and 1.0 indicating the forms have high parallel test reliability in measuring the same attribute, while correlations lower than 0.8 represent low parallel test reliability.

1. Parallel Test Reliability with Surveys

2. Parallel Test Reliability with Surveys
Students take
Form 1 of the
Survey

3. Parallel Test Reliability with Surveys
Respondent Average Score
Bob 3.5
Fred 2.7
Sally 4.2
Zelda 6.1
Here are the results

4. Parallel Test Reliability with Surveys
The same students take
Form 2 of the Survey
usually at the same time

5. Parallel Test Reliability with Surveys
Form 2 has different items
than Form 1 but the items are
designed to target the same
construct.
The same students take
Form 2 of the Survey
usually at the same time

6. Parallel Test Reliability with Surveys
Here are the results
Respondent Average Score
Bob 3.7
Fred 2.5
Sally 4.5
Zelda 5.8
The same students take
Form 2 of the Survey
usually at the same time

7. Parallel Test Reliability with Surveys
Respondent Average Score
Bob 3.7
Fred 2.5
Sally 4.5
Zelda 5.8
Respondent Average Score
Bob 3.5
Fred 2.7
Sally 4.2
Zelda 6.1
Results on Form A Results on Form B

8. Parallel Test Reliability with Surveys
Respondent Average Score
Bob 3.7
Fred 2.5
Sally 4.5
Zelda 5.8
Respondent Average Score
Bob 3.5
Fred 2.7
Sally 4.2
Zelda 6.1
Results on Form A Results on Form B
We, then, correlate the results. Higher
correlations (.8 to 1.0) signify high Parallel Test
Reliability. Anything lower than .8 signify low
Parallel Test Reliability.