Planetary Health in Health Guidelines and Health Technology Assessments: A Scoping Review.

Introduction: Individual human health is inextricably linked to planetary health, which refers to the health of human civilization and the natural systems on which it depends. These systems are captured by the nine planetary boundaries which together define a safe operating space for humanity. The health sector contributes to the transgression of these boundaries, thereby jeopardizing both individual and planetary health. However, there is a growing interest in the health sector in incorporating the preservation of planetary boundaries into health guidelines and health technology assessments (HTAs), which synthesize evidence and guide healthcare decisions. Methods: This scoping review aims to describe methodological guidance and considerations for incorporating planetary health in health guidelines and HTAs. We conducted a scoping review adhering to the JBI methodology including articles from several databases since inception until September 2023. We used narrative synthesis and descriptive statistics to describe eligible studies. Results: Of the 38 included studies, 14 (37%) were commentaries, six (16%) were methodological papers, and four (10·5%) were health guidelines. Included studies focused primarily on greenhouse gas emissions as an outcome. The included health guidelines were rated at a median of 52% (range: 16% to 67%) on AGREE II for methodological quality. Discussion: Key findings pertain to the normative significance of planetary health in guidelines and HTAs, scope and quality of included studies, inconsistencies in methods, and challenges in implementation. These findings will inform future Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) guidance on planetary health. Registration: A protocol of this scoping review was registered in Open Science Framework (https://osf.io/3jmsa) and published in the journal Systematic Reviews (10.1186/s13643-024-02577-2).