Which two methods for estimating reliability require two testing sessions?

Question

Quizplus · Accepted Answer

Test-retest and parallel-form methods both require two testing sessions to obtain estimates of reliability. The test-retest method involves administering the same test to the same group of people on two different occasions and correlating the scores obtained at each administration. The parallel-form method involves administering two versions of the same test to the same group of people and correlating the scores obtained on each version. The other options, interobserver and correlation coefficient, do not require two testing sessions.

Which Two Methods for Estimating Reliability Require Two Testing Sessions