Abstract
The purpose of this study was to investigate the repetition effect of Uchida-Kraepelin Psychodiagnostic Test, when administered annually at school. To clarify the repetition effect, performance of junior high school students was compared for three consecutive years. The increase in the amount of work done was 10.1% for the second year, and 18.1% for the third, when compared with the first year trial. To investigate the repetition effect at different test intervals, changes in the amount of work over trials at three intervals, 1 month, 6 months, and 12 months, were examined. The repetition effect was strongest at the interval of 1 month, and was weakest at 12 months. The finding suggested that when interpreting test results, changes in performance could be important, but previous experience and when it had been should also be taken into account.
