We read with interest the recent systematic review and meta-analysis by Magi et al. (2026) that synthesises evidence on the relationship between health literacy (HL) and self-care behaviours in patients with chronic diseases. Chronic disease management faces persistent challenges, including poor treatment adherence, recurrent exacerbations, preventable hospitalisations and rising healthcare costs. Low HL significantly contributes to these issues by impairing patients' ability to access, understand and apply health information, thereby reducing effective self-management. With increasing multimorbidity, socioeconomic disparities and population ageing, these unmet clinical needs have become more pressing. Although the reviewed meta-analysis consolidates observational data showing a moderate positive association between HL and self-care behaviours across various conditions, several key limitations in the current synthesis and broader field limit its direct translation into effective nursing interventions and policy. A major limitation is the heavy reliance on cross-sectional designs. While useful for detecting associations, such studies cannot determine causality or directionality. It remains uncertain whether higher HL directly improves self-care (maintenance, monitoring and management), whether successful self-care experiences enhance HL through learning, or whether both are driven by shared factors such as education, cognition, or healthcare access. Bidirectional effects and residual confounding are plausible but underexplored. As noted in a heart failure study, cross-sectional designs explicitly ‘preclude establishing causal relationships between HL and self-care behaviours’ (Santillan-Garcia et al. 2026). Prospective longitudinal studies with repeated measures are urgently needed to clarify temporality and guide timely HL screening and intervention in clinical practice. Another critical gap lies in translating associations into effective interventions. Although the review identifies psychological, cognitive and social mediators as well as distress and depression as moderators, evidence for interventions that meaningfully improve self-care via HL enhancement remains limited and heterogeneous. A meta-analysis of randomised controlled trials (RCTs) on HL interventions demonstrated moderate improvements in HL levels (SMD 0.75), health status and self-efficacy, yet effects on disease-specific self-care behaviours were inconsistent, stronger in hypertension than in diabetes or COPD and often diminished after three months (Shao et al. 2023). This indicates that improving HL alone does not guarantee sustained gains in self-care domains or hard clinical outcomes such as reduced hospitalisations. As a full-time medical researcher in this field, I suggest that future interventions should be theory-driven, integrating behavioural change techniques, culturally tailored materials and digital tools adapted to diverse literacy levels, while explicitly addressing identified moderators and focusing on long-term maintenance. Methodological quality and implementation issues further hinder progress. A meta-analysis of self-care interventions across chronic conditions reported only modest efficacy, with high heterogeneity and frequent risk of bias stemming from inadequate sample sizes, poor fidelity and limited long-term follow-up (Lee et al. 2022). Similar concerns, including high risk of bias and low-to-moderate GRADE ratings, are evident in the current review. These shortcomings reflect a broader translational bottleneck: correlational evidence is growing, but rigorously designed RCTs that combine HL strategies with comprehensive self-care support and evaluate objective clinical outcomes remain scarce. Implementation research on embedding HL assessment into routine nursing care, particularly in resource-limited settings, is equally underdeveloped. Multimorbidity adds further complexity. A recent systematic review found that low HL is consistently associated with higher odds of multimorbidity, mediated partly by self-efficacy and influenced by socioeconomic factors (Chauhan et al. 2024). However, intervention studies in multimorbid patients are rare and outcomes rarely address the compounded challenges of polypharmacy and conflicting regimens. Expanding research with subgroup analyses by comorbidity burden would better reflect real-world practice and support precision nursing strategies. In summary, Magi et al. offer a valuable synthesis confirming a moderate HL-self-care association. Nevertheless, advancing the field requires moving beyond descriptive correlations toward causal evidence, optimised theory-based interventions and equitable implementation. Such efforts could transform HL into a practical lever for better self-care and reduced chronic disease burden. All work was conducted independently by the authors. Generative AI tools (Deepseek) were employed solely for the purpose of language polishing and stylistic refinement. These tools played no role in the study's conception, design, data analysis, interpretation, or the generation of scientific content. The authors assume full responsibility for the intellectual substance, accuracy and originality of the work and have thoroughly reviewed and approved the final manuscript. The authors have nothing to report. The authors have nothing to report. The authors have nothing to report. The authors declare no conflicts of interest. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.
Wang et al. (Mon,) studied this question.