Health literacy (HL) is defined as the ability to access, understand, evaluate and apply health-related information, which can influence individuals’ health outcomes. Blue-collar workers, who often have lower educational attainment and experience language barriers, are at increased risk of limited HL. This systematic review aims to assess the prevalence of limited HL among blue-collar workers to inform the development of appropriate interventions for its improvement.

The systematic review will assess the prevalence of limited HL among blue-collar workers. We will include all quantitative study designs using any instrument for measuring general HL. We will exclude studies that focus on specific types of HL and specific health conditions. We have performed a literature search from inception up to 30 April 2025, in the Medline, Embase, CINAHL, Web of Science and Cochrane Central Register of Controlled Trials (CENTRAL) databases. We will also search eligible articles from Google Scholar and Open Grey as sources of unpublished studies/gray literature. Two independent reviewers will conduct the primary screening of articles, data extraction and quality assessment (using the Cochrane risk-of-bias tool for randomised trials and risk of bias in non-randomised studies of exposure), with a third individual available to resolve conflicts. We will assess heterogeneity using the ² test and I² test. If there is sufficient homogeneity, we will pool studies in a meta-analysis or summarise the findings narratively if heterogeneity is too high. We will use a random effects model for our analysis, and we will use funnel plots to evaluate potential publication bias. The Grading of Recommendations Assessment, Development and Evaluation approach will be used to assess the certainty of findings.

Ethical approval will not be required for this review as there is no primary data collection involving humans. The results will be published in a peer-reviewed journal and presented at relevant conferences.

CRD42024597732.