Intentional and Incidental Learning with Instructional Texts: A Meta-Analysis for 1970–1980

Twenty-three research reports were selected based on five predetermined criteria. This led to 52 comparisons in which an experimental group was compared with its corresponding control group. Effect size estimators and their confidence intervals were calculated using methods developed by Glass (1977) , Hedges and Olkin (1980) , and Hedges (1981) . The main findings of the meta-analysis were the following: Giving behavioral objectives, learning directions, or questions before an instructional text is read leads to some improvement in the learning of goal relevant material; however, these preinstructional acts impede the learning of goal irrelevant material. It was concluded that overall learning is slightly improved by these acts. Some variables seem to have a modifying influence on the learning of goal relevant material and of goal irrelevant material (e.g., variables such as text length, objective type, test difficulty, etc). To a certain extent the results have supported the information processing theory of intentional and incidental learning.