Ecological validity of adjunct questions in a college biology course

Abstract

To validate their use in a natural environment with realistic learning materials and conditions, the efficacy of adjunct questions was tested in a college biology course with a double-crossover design. Mixed results were obtained. On the one hand, students using adjunct questions during the second half of the course scored significantly higher than control students on a variety of measures obtained on the final examination. Significant indirect as well as direct effects were obtained, and significant effects were demonstrated on comprehension as well as verbatim-recall examination questions. On the other hand, during the first half of the course evidence was also obtained that some students did not follow instructions on the proper use of adjunct questions, and that for those students adjunct questions actually impaired learning. Such vagaries may be common in natural experimental settings as opposed to highly controlled laboratory settings. It is concluded that, rather than requiring all students to use adjunct questions, it would be better to make them optional. Presumably, adjunct questions would be used, under an optional condition, only by students who were motivated to use them properly after receiving strong warnings concerning their possible misuse.