Purpose This study examines the effects of an Information-Based Writing Portfolio Assessment (IbWPA) on undergraduate students’ information literacy (IL) self-efficacy and explores how writing motivation shapes these outcomes. While prior studies have integrated IL instruction into writing tasks, most assessments focus on written products rather than the reasoning processes underlying students’ use of information. Design/methodology/approach Eighty-one third-year English majors at a university in Macau participated in a 14-week instructional intervention integrating sequenced writing assignments, reflective information statements, and portfolio-based assessment. The information statements required students to explain the credibility and relevance of sources used in their writing, enabling a more process-oriented assessment of information practices. Paired-samples t-tests and linear mixed-effects models were used to analyze changes in IL self-efficacy and the role of motivation. Findings Results showed significant increases in basic and advanced IL self-efficacy, while intermediate IL self-efficacy did not change significantly. Motivation positively predicted IL self-efficacy across all levels, and interaction effects indicated that students with lower baseline motivation experienced larger gains in basic IL self-efficacy. Research limitations/implications As a single-group pre–post study, causal interpretations should be cautiously made. Future research may examine similar interventions across disciplines and instructional contexts. Originality/value The study introduces the IbWPA model, which extends portfolio-based writing assessment by incorporating reflective information statements that capture students’ evaluative reasoning about sources. The findings highlight how process-oriented assessment can support the development of students’ confidence in performing information literacy practices.
Yu et al. (Wed,) studied this question.