National Planetary Health learning objectives for Germany: A steppingstone for medical education to promote transformative change

Physicians play an important role in adapting to and mitigating the adverse health effects of the unfolding climate and ecological crises. To fully harness this potential, future physicians need to acquire knowledge, values, skills, and leadership attributes to care for patients presenting with environmental change-related conditions and to initiate and propel transformative change in healthcare and other sectors of society including, but not limited to, the decarbonization of healthcare systems, the transition to renewable energies and the transformation of transport and food systems. Despite the potential of Planetary Health Education (PHE) to support medical students in becoming agents of change, best-practice examples of mainstreaming PHE in medical curricula remain scarce both in Germany and internationally. The process of revising and updating the Medical Licensing Regulations and the National Competency-based Catalog of Learning Objectives for Medical Education in Germany provided a window of opportunity to address this implementation challenge. In this article, we describe the development and content of national Planetary Health learning objectives for Germany. We anticipate that the learning objectives will stimulate the development and implementation of innovative Planetary Health teaching, learning and exam formats in medical schools and inform similar initiatives in other health professions. The availability of Planetary Health learning objectives in other countries will provide opportunities for cross-country and interdisciplinary exchange of experiences and validation of content, thus supporting the consolidation of Planetary Health learning objectives and the improvement of PHE for all health professionals globally.

Physicians play an important role in adapting to and mitigating the adverse health e ects of the unfolding climate and ecological crises. To fully harness this potential, future physicians need to acquire knowledge, values, skills, and leadership attributes to care for patients presenting with environmental change-related conditions and to initiate and propel transformative change in healthcare and other sectors of society including, but not limited to, the decarbonization of healthcare systems, the transition to renewable energies and the transformation of transport and food systems. Despite the potential of Planetary Health Education (PHE) to support medical students in becoming agents of change, best-practice examples of mainstreaming PHE in medical curricula remain scarce both in Germany and internationally. The process of revising and updating the Medical Licensing Regulations and the National Competency-based Catalog of Learning Objectives for Medical Education in Germany provided a window of opportunity to address this implementation challenge. In this article, we describe the development and content of national Planetary Health learning objectives for Germany. We anticipate that the learning objectives will stimulate the development and implementation of innovative Planetary Health teaching, learning and exam formats in medical schools and inform similar initiatives in other health professions. The availability of Planetary Health learning objectives in other countries will provide opportunities for cross-country and interdisciplinary exchange of experiences and validation of content, thus supporting the consolidation of Planetary Health learning objectives and the improvement of PHE for all health professionals globally.

. Introduction
The anthropogenic climate crisis and the transgression of other planetary boundaries including biodiversity loss, aberrant biogeochemical flows and pollution are the greatest threats to public health in the twenty-first century (1). Adverse health effects include increased morbidity and mortality due to extreme weather events such as floods and heat waves, changing patterns of vector-borne diseases, altered prevalences of non-communicable conditions like asthma and other atopic diseases and adverse effects on mental health (2). The interdependence between the climate and ecological crises, societal, political, and economic systems as well as health and wellbeing are at the core of the emerging concept of Planetary Health, defined as "the health of human civilization and the state of the natural systems on which it depends" (3). Mirroring this interdependence, most adaptation and mitigation policies including the transformation of transport, energy, and agri-food systems are associated with substantial health co-benefits by, inter alia, reducing air pollution, increasing physical activity, and improving nutrition.
Physicians play an important role in adapting to and mitigating the climate and ecological crises and thus in attenuating adverse health effects. This includes, but is not limited to, addressing risk factors associated with the climate and ecological crises in medical histories and anticipatory guidance, building expertise in the treatment of climate-sensitive health conditions and implementing policies to decarbonize healthcare systems. The contribution of physicians to adaptation and mitigation is based on a professional ethos emphasizing their responsibility for the wellbeing of individuals and populations now and in the future (4), high levels of trust among the general public (5,6) and their role as advocates for health-promoting climate policies (7). Planetary Health Education (PHE) aims at equipping physicians with knowledge, attitudes, values, and skills to fully harness this potential. To strengthen the role of physicians as change agents in healthcare institutions and other sectors of society, PHE moreover stimulates the development of leadership attributes, confidence and systems thinking skills (8)(9)(10). While the urgency to integrate PHE into medical curricula has been frequently expressed (10)(11)(12), best-practice examples of mainstreaming PHE in medical curricula remain scarce both in Germany and internationally (13)(14)(15)(16). To date, PHE in medical schools is mostly limited to student-driven extra-curricular lecture series and elective courses (17), with a majority of courses only available in English and targeting healthcare professionals from the global north (18).
In Germany, the National Competency-based Catalog of Learning Objectives for Medical Education (hereinafter referred to as National Catalog of Learning Objectives; Nationaler Kompetenzbasierter Lernzielkatalog Medizin, NKLM), first published in 2015 by the Association of Medical Faculties in Germany, is currently refined in a nationwide multi-stakeholder process. It consists of a mandatory core curriculum and is accompanied by several non-mandatory but thematically cross-cutting chapters that can be covered by medical schools. Paralleling the refinement of the National Catalog of Learning Objectives, the German Medical Licensing Regulations are currently updated. After approval by the Federal Council, both documents will provide the legal foundation for the structure and content of medical education in Germany. It is currently anticipated that both documents will go into effect in 2025 and will stimulate changes to the curricula of all medical schools such as strengthening primary and outpatient care and enabling clinical electives in local public health departments. The update of the Medical Licensing Regulations and the National Catalog of Learning Objectives constituted a unique window of opportunity to address the lack of PHE in German medical curricula by developing national Planetary Health learning objectives. Given their impact on curriculum design, we anticipate that the learning objectives will stimulate the development and implementation of innovative teaching, learning and exam formats in medical schools. Further background information on medical education in Germany and current reform processes is presented in Appendix 1 in the Supplementary material. In this article, we describe the development and content of national Planetary Health learning objectives that adhere to the structural requirements of the National Catalog of Learning Objectives. We hope that the catalog of learning objectives will inspire similar activities in other (health-related) disciplines and countries.

. Iterative development of national Planetary Health learning objectives
The development of a catalog of national Planetary Health learning objectives proceeded iteratively. Initially, an ad hoc task force comprised of seven medical students and two early

Urgency and scale
The field of planetary health is driven by the scale of environmental change, its effects on human health, and the urgency with which the global population must respond. Students should be able to examine the complexity of interactions between the geographical scale, temporal scale, socioeconomic factors, and political and cultural context that shape specific challenges to and potential solutions for sustainable human health outcomes.

Inequality and inequity
Understanding the differences between equality and equity in theory and practice, and concepts of marginalization, vulnerability, resilience, and who benefits and is harmed in a given scenario, is a core objective of planetary health teaching. Since the effects of environmental change on human health are heterogeneous and mediated by factors such as geographical scale, temporal scale, socioeconomic factors, and political and cultural context, students should think critically about whose health is at stake and how it is measured.

Global citizenship and cultural identity
A global citizen is someone who sees themselves as part of the international community and whose actions help define the community's values and practices. If students can realize their own cultural identities and recognize their inherent membership in both their local and global communities, they have the opportunity to help define the values and practices of the next generation to positively affect those communities. career health professionals with expertise in PHE were invited by the Association of Medical Faculties in Germany in 2020 to develop a set of competency-based Planetary Health learning objectives for the non-mandatory part of the National Catalog of Learning Objectives. Given that no widely used Planetary Health learning objectives were available in 2020, the task force developed an initial set of learning objectives as well as superordinate competencies and sub-competencies based on their expertise in PHE including the development and implementation of Planetary Health elective courses. Based on this initial set, we iteratively revised, restructured, and expanded the learning objectives in five steps. First, to improve the structure of the initial set of learning objectives, the taskforce-now consisting of four medical students and three early career health professionals with expertise in PHE-structured the learning objectives and the superordinate competencies and sub-competencies into different levels. Guided by prior work in medical education research (8), we applied the following levels of learning: (1) knowledge, (2) values and attitudes, and (3) transformative skills (Table 1).
Second, to improve the comprehensiveness of the initial set of learning objectives, we expanded the set based on seminal contributions to the emerging field of Planetary Health and PHE. Two members of the task force independently mapped the learning objectives against the 12 Cross-cutting principles of planetary health education, a set of foundational principles proposed to guide teaching in the field of Planetary Health (Table 2) (19). In addition, one member of the task force reviewed three additional documents, (1) the first Planetary Health textbook (20), (2)  Third, the refined catalog of Planetary Health learning objectives was subjected to a first round of external peer review by two university professors for Global Health and Health and Climate Change in Germany, respectively. Based on their comments and feedback, we further refined the learning objectives.
Fourth, given that the Planetary Health learning objectives are part of the non-mandatory but cross-cutting chapters of the National Catalog of Learning Objectives, we established links to the mandatory core curriculum to showcase the relevance of Planetary Health to other medical subject areas. To this end we (1) implemented cross-references between learning objectives in the Planetary Health catalog and the core curriculum and (2) added examples pertinent to Planetary Health to learning objectives in the core curriculum. Initially, we identified learning objectives suitable for cross-linking and adding Planetary Health examples by a double-blinded screening of the core curriculum. Next, we reached consensus in pairs and the entire task force on which learning objectives were to be linked and the wording and location of Planetary Health examples to be included in the core curriculum, respectively. Finally, we sought approval from the chapter authors of the core curriculum for integrating Planetary Health examples in their chapters.
In 2021, the Institute for Medical and Pharmaceutical Examinations (Institut für Medizinische und Pharmazeutische Prüfungsfragen, IMPP), responsible for developing and administering centralized state examinations, established an interdisciplinary working group on Climate, Environment and Health Impact Assessment (22) coordinated by two members of the task force (EMS and ME). The working group aims at informing and leading on the development of Planetary Health-related exam questions to be included in state examinations for physicians and other health professionals and is comprised of experts with a broad spectrum of expertise including different medical specialties, psychology, psychotherapy, sociology, and transition research. In a fifth and final step, members of the working group reviewed the Planetary Health learning objectives and suggested further refinements based on several rounds of discussions within the working group. Refinements were mostly focused on concretizing content of specific learning objectives and examples. The final catalog of national Planetary Health learning objectives was published together with the core curriculum in July 2021 and is now available online (23). An English translation

. Conclusions and next steps
To our knowledge, the catalog of national Planetary Health learning objectives is the first attempt to operationalize general principles of PHE and to develop a catalog of actionable learning objectives for medical education in Germany. Following the principle of constructive alignment, defined here as the alignment of teaching, and learning activities and assessment tasks with intended learning objectives (24), we anticipate that the Planetary Health learning objectives will support the development and implementation of innovative Planetary Health teaching, learning and exam formats in medical schools. Complementing local initiatives in medical schools, the adaptation of national state examinations based on the catalog of Planetary Health learning objectives is a promising lever to stimulate PHE in medical schools, independent of local initiatives. The activities described in this article complement a small number of similar initiatives internationally (25)(26)(27)(28). The availability of other PHE catalogs will provide opportunities for cross-country and interdisciplinary exchange of experiences and validation of content, thus supporting the consolidation of Planetary Health learning objectives and alignment of PHE for all health professionals.
Given the increasing health impacts of the climate and ecological crises (2), we expect a growing interest from policy and health systems stakeholders in actions to adapt to and mitigate these crises in the healthcare sector, in Germany and internationally. This is underscored, inter alia, by the adoption of several motions at the annual meeting of the German Medical Association, including a motion on the integration of Planetary Health in continuous professional education (29). PHE guided by the national Planetary Health learning objectives has the potential to equip physicians with the knowledge, values, skills, confidence, and leadership attributes to adequately respond to the climate and ecological crises. We are glad to share our experiences with interested individuals and organizations worldwide and are grateful for any feedback that stimulates the refinement of the current version of the national Planetary Health learning objectives for Germany.

Data availability statement
The original contributions presented in the study are included in the article/Supplementary material. Further inquiries can be directed to the corresponding author.

Author contributions
KW wrote the first draft of the manuscript. E-MS-S and ME provided substantial conceptual input to the manuscript. All authors critically reviewed the different versions of the manuscript, suggested revisions, and approved the version to be published.

Funding
This publication was supported by the Open Access Publication Fund of the University of Wuerzburg.