Anne Fleur Kortekaas-Rijlaarsdam

CHAPTER 2 30 Measures and Data Extraction Table E2.2 in supplementary material gives an overview of tasks and questionnaires used to assess academic outcomes, an overview of the selected mediator and moderator variables, as well as the measures derived from the academic tasks. Academic outcomes Articles were included if they provided information about either accuracy or productivity scores for math, reading or spelling, or a combination of these. When mean accuracy and productivity scores were not reported as dependent variables, they were calculated by hand. Accuracy was calculated by dividing the mean number correct responses by the mean number items completed. Productivity was calculated by dividing the mean number of items completed by the total number of items. Figure 2.1 Flow diagram of the meta-analytic search and study selection