Students’ online credibility evaluation skills across four grades representing three educational levels: factorial invariance and cross-sectional comparisons

We sought to validate a web-based online credibility evaluation task across four grade levels to provide a robust tool for assessing students’ online credibility evaluation skills and grade-level differences in skills while controlling for text reading order, prior topic knowledge, and reading fluency. The sample comprised 728 students from primary (fourth and sixth graders), lower secondary (eighth graders), and upper secondary (10th graders) education in Finland. Students evaluated four online texts representing different genres: a popular science text, a science newspaper article, a layperson’s blog text, and a commercial text. Each text was evaluated from three perspectives: author expertise, author benevolence, and quality of evidence. The results confirmed the factorial invariance of the task across grade levels, supporting the validity of comparisons between the grade levels. Older students performed higher than younger ones in evaluating less credible online texts (i.e., the blog and commercial text). By offering a theoretically grounded and methodologically robust evaluation approach, our findings contribute to advancing assessment practices in the digital age.