“…However, comparisons should be made cautiously due to weak measures of nonformal and formal AET. After all, some studies show literacy gains in nonformal basic skill courses ( de Greef, Segers & Verté, 2012;de Greef, Verté & Segers, 2015). Overall, this study confirms the results from previous research (e.g., Desjardins, 2003;Green & Riddell, 2012;OECD, 2013a), showing that informal literacy learning, particularly outside of work, complements initial education's effect on literacy proficiency, but does not outweigh its impact or that of other background variables.…”