This article builds on research regarding response shift effects and retrospective self-report ratings. Results suggest moderate evidence of a response shift bias in the conventional pretest-posttest treatment design in the treatment group. The use of explicitly worded anchors on response scales, as well as the measurement of knowledge ratings (a cognitive construct) in an evaluation methodology setting, helped to mitigate the magnitude of a response shift bias. The retrospective pretest-posttest design provides a measure of change that is more in accord with the objective measure of change than is the conventional pretest-posttest treatment design with the objective measure of change, for the setting and experimental conditions used in the present study.
Nakonezny, Paul A. and Rodgers, Joseph Lee
"An Empirical Evaluation Of The Retrospective Pretest: Are There Advantages To Looking Back?,"
Journal of Modern Applied Statistical Methods:
1, Article 22.
Available at: http://digitalcommons.wayne.edu/jmasm/vol4/iss1/22