🏷️MeSH Category Trends
Every MeSH level-2 category's share of the papers month by month, Jan 2024 – Sep 2026, up to three years back. A paper counts for a category when any of its MeSH headings sits under it.
111 of 111 categories
| Code | Category | Level 1 | Jan 2024 – Sep 2026 | Last 12 mo | Prior 12 mo | Change (pp) |
|---|---|---|---|---|---|---|
| C10 | Nervous System Diseases | Diseases | 14.1% | 12.8% | +1.30 | |
| G17 | Mathematical Concepts | Phenomena and Processes | 10.1% | 8.9% | +1.15 | |
| H01 | Natural Science Disciplines | Disciplines and Occupations | 8.8% | 7.7% | +1.08 | |
| D20 | Complex Mixtures | Chemicals and Drugs | 14.4% | 13.3% | +1.04 | |
| G05 | Genetic Phenomena | Phenomena and Processes | 11.2% | 10.3% | +0.88 | |
| A15 | Hemic and Immune Systems | Anatomy | 6.8% | 5.9% | +0.86 | |
| L01 | Information Science | Information Science | 18.5% | 17.8% | +0.71 | |
| C20 | Immune System Diseases | Diseases | 8.6% | 7.9% | +0.69 | |
| C01 | Infections | Diseases | 9.4% | 8.8% | +0.66 | |
| G12 | Immune System Phenomena | Phenomena and Processes | 3.1% | 2.6% | +0.49 | |
| A08 | Nervous System | Anatomy | 4.6% | 4.1% | +0.46 | |
| D12 | Amino Acids, Peptides, and Proteins | Chemicals and Drugs | 40.8% | 40.4% | +0.43 | |
| B04 | Viruses | Organisms | 4.5% | 4.0% | +0.43 | |
| B03 | Bacteria | Organisms | 5.1% | 4.7% | +0.40 | |
| G11 | Musculoskeletal and Neural Physiological Phenomena | Phenomena and Processes | 4.2% | 3.8% | +0.35 | |
| C22 | Animal Diseases | Diseases | 5.6% | 5.2% | +0.35 | |
| G16 | Biological Phenomena | Phenomena and Processes | 6.3% | 6.0% | +0.35 | |
| G06 | Microbiological Phenomena | Phenomena and Processes | 3.3% | 3.0% | +0.33 | |
| C12 | Urogenital Diseases | Diseases | 10.0% | 9.7% | +0.30 | |
| A11 | Cells | Anatomy | 25.0% | 24.8% | +0.29 | |
| C15 | Hemic and Lymphatic Diseases | Diseases | 4.3% | 4.0% | +0.26 | |
| C05 | Musculoskeletal Diseases | Diseases | 4.1% | 3.8% | +0.24 | |
| C04 | Neoplasms | Diseases | 27.0% | 26.9% | +0.17 | |
| C16 | Congenital, Hereditary, and Neonatal Diseases and Abnormalities | Diseases | 3.0% | 2.9% | +0.14 | |
| K01 | Humanities | Humanities | 2.2% | 2.1% | +0.14 | |
| C07 | Stomatognathic Diseases | Diseases | 1.9% | 1.8% | +0.11 | |
| G15 | Plant Physiological Phenomena | Phenomena and Processes | 0.3% | 0.2% | +0.11 | |
| C23 | Pathological Conditions, Signs and Symptoms | Diseases | 25.7% | 25.6% | +0.11 | |
| N02 | Health Care Facilities Workforce and Services | Health Care | 10.2% | 10.1% | +0.10 | |
| A14 | Stomatognathic System | Anatomy | 1.0% | 0.9% | +0.09 | |
| A05 | Urogenital System | Anatomy | 2.2% | 2.1% | +0.08 | |
| E03 | Anesthesia and Analgesia | Techniques and Equipment | 0.4% | 0.3% | +0.08 | |
| B05 | Organism Forms | Organisms | 0.6% | 0.5% | +0.06 | |
| G08 | Reproductive and Urinary Physiological Phenomena | Phenomena and Processes | 3.1% | 3.0% | +0.06 | |
| A06 | Endocrine System | Anatomy | 0.8% | 0.8% | +0.06 | |
| F03 | Mental Disorders | Psychiatry and Psychology | 4.2% | 4.1% | +0.06 | |
| E06 | Dentistry | Techniques and Equipment | 0.8% | 0.7% | +0.05 | |
| C09 | Otorhinolaryngologic Diseases | Diseases | 1.2% | 1.1% | +0.05 | |
| D25 | Biomedical and Dental Materials | Chemicals and Drugs | 7.1% | 7.0% | +0.05 | |
| F04 | Behavioral Disciplines and Activities | Psychiatry and Psychology | 1.3% | 1.2% | +0.04 | |
| A13 | Animal Structures | Anatomy | 0.2% | 0.2% | +0.03 | |
| A16 | Embryonic Structures | Anatomy | 0.6% | 0.6% | +0.03 | |
| G10 | Digestive System and Oral Physiological Phenomena | Phenomena and Processes | 0.6% | 0.6% | +0.03 | |
| A04 | Respiratory System | Anatomy | 1.1% | 1.1% | +0.03 | |
| C26 | Wounds and Injuries | Diseases | 2.8% | 2.8% | +0.02 | |
| C06 | Digestive System Diseases | Diseases | 9.9% | 9.9% | +0.02 | |
| A21 | Viral Structures | Anatomy | 0.1% | 0.0% | +0.02 | |
| I01 | Social Sciences | Anthropology, Education, Sociology | 5.1% | 5.1% | +0.01 | |
| A03 | Digestive System | Anatomy | 3.4% | 3.4% | +0.01 | |
| A20 | Bacterial Structures | Anatomy | 0.7% | 0.7% | +0.01 | |
| A19 | Fungal Structures | Anatomy | 0.1% | 0.0% | +0.01 | |
| B02 | Archaea | Organisms | 0.0% | 0.0% | +0.00 | |
| C21 | Disorders of Environmental Origin | Diseases | 0.0% | 0.0% | +0.00 | |
| C24 | Occupational Diseases | Diseases | 0.1% | 0.1% | +0.00 | |
| D13 | Nucleic Acids, Nucleotides, and Nucleosides | Chemicals and Drugs | 5.7% | 5.7% | +0.00 | |
| C25 | Chemically-Induced Disorders | Diseases | 1.4% | 1.4% | −0.00 | |
| J02 | Food and Beverages | Technology, Industry, Agriculture | 2.2% | 2.2% | −0.02 | |
| I02 | Education | Anthropology, Education, Sociology | 1.3% | 1.3% | −0.04 | |
| G13 | Integumentary System Physiological Phenomena | Phenomena and Processes | 0.5% | 0.5% | −0.04 | |
| G04 | Cell Physiological Phenomena | Phenomena and Processes | 16.6% | 16.7% | −0.04 | |
| A12 | Fluids and Secretions | Anatomy | 1.5% | 1.6% | −0.09 | |
| G09 | Circulatory and Respiratory Physiological Phenomena | Phenomena and Processes | 3.3% | 3.4% | −0.09 | |
| F02 | Psychological Phenomena | Psychiatry and Psychology | 4.1% | 4.2% | −0.10 | |
| A01 | Body Regions | Anatomy | 1.6% | 1.7% | −0.12 | |
| F01 | Behavior and Behavior Mechanisms | Psychiatry and Psychology | 7.0% | 7.1% | −0.13 | |
| H02 | Health Occupations | Disciplines and Occupations | 2.9% | 3.0% | −0.14 | |
| N03 | Health Care Economics and Organizations | Health Care | 3.2% | 3.3% | −0.14 | |
| J03 | Non-Medical Public and Private Facilities | Technology, Industry, Agriculture | 0.1% | 0.3% | −0.15 | |
| C17 | Skin and Connective Tissue Diseases | Diseases | 7.8% | 8.0% | −0.16 | |
| A09 | Sense Organs | Anatomy | 1.2% | 1.4% | −0.17 | |
| I03 | Human Activities | Anthropology, Education, Sociology | 1.8% | 1.9% | −0.18 | |
| N04 | Health Services Administration | Health Care | 18.9% | 19.1% | −0.18 | |
| A07 | Cardiovascular System | Anatomy | 2.5% | 2.7% | −0.18 | |
| D10 | Lipids | Chemicals and Drugs | 5.3% | 5.6% | −0.21 | |
| C11 | Eye Diseases | Diseases | 2.5% | 2.7% | −0.22 | |
| A17 | Integumentary System | Anatomy | 1.0% | 1.2% | −0.23 | |
| A10 | Tissues | Anatomy | 4.8% | 5.0% | −0.25 | |
| G14 | Ocular Physiological Phenomena | Phenomena and Processes | 0.8% | 1.0% | −0.28 | |
| D01 | Inorganic Chemicals | Chemicals and Drugs | 11.7% | 12.0% | −0.31 | |
| G01 | Physical Phenomena | Phenomena and Processes | 7.6% | 7.9% | −0.31 | |
| C08 | Respiratory Tract Diseases | Diseases | 7.7% | 8.0% | −0.35 | |
| A02 | Musculoskeletal System | Anatomy | 3.0% | 3.3% | −0.36 | |
| Z01 | Geographic Locations | Geographicals | 13.5% | 13.9% | −0.38 | |
| N06 | Environment and Public Health | Health Care | 44.6% | 45.0% | −0.38 | |
| E07 | Equipment and Supplies | Techniques and Equipment | 5.4% | 5.8% | −0.38 | |
| A18 | Plant Structures | Anatomy | 1.5% | 1.9% | −0.40 | |
| E04 | Surgical Procedures, Operative | Techniques and Equipment | 12.1% | 12.5% | −0.40 | |
| N01 | Population Characteristics | Health Care | 6.0% | 6.5% | −0.44 | |
| D23 | Biological Factors | Chemicals and Drugs | 22.3% | 22.7% | −0.45 | |
| G03 | Metabolism | Phenomena and Processes | 12.7% | 13.3% | −0.52 | |
| D06 | Hormones, Hormone Substitutes, and Hormone Antagonists | Chemicals and Drugs | 4.1% | 4.7% | −0.56 | |
| D04 | Polycyclic Compounds | Chemicals and Drugs | 6.3% | 6.9% | −0.61 | |
| G02 | Chemical Phenomena | Phenomena and Processes | 22.0% | 22.6% | −0.61 | |
| N05 | Health Care Quality, Access, and Evaluation | Health Care | 43.0% | 43.7% | −0.64 | |
| D05 | Macromolecular Substances | Chemicals and Drugs | 9.0% | 9.6% | −0.67 | |
| B01 | Eukaryota | Organisms | 96.4% | 97.2% | −0.79 | |
| C14 | Cardiovascular Diseases | Diseases | 9.5% | 10.3% | −0.83 | |
| E05 | Investigative Techniques | Techniques and Equipment | 69.2% | 70.1% | −0.85 | |
| J01 | Technology, Industry, and Agriculture | Technology, Industry, Agriculture | 17.4% | 18.3% | −0.89 | |
| D26 | Pharmaceutical Preparations | Chemicals and Drugs | 16.0% | 16.9% | −0.90 | |
| D08 | Enzymes and Coenzymes | Chemicals and Drugs | 15.9% | 17.0% | −1.06 | |
| E01 | Diagnosis | Techniques and Equipment | 35.9% | 37.1% | −1.19 | |
| D09 | Carbohydrates | Chemicals and Drugs | 13.9% | 15.1% | −1.24 | |
| D02 | Organic Chemicals | Chemicals and Drugs | 23.1% | 24.5% | −1.43 | |
| C19 | Endocrine System Diseases | Diseases | 11.4% | 12.9% | −1.50 | |
| D03 | Heterocyclic Compounds | Chemicals and Drugs | 17.4% | 19.2% | −1.79 | |
| C18 | Nutritional and Metabolic Diseases | Diseases | 13.8% | 15.7% | −1.87 | |
| G07 | Physiological Phenomena | Phenomena and Processes | 26.7% | 28.6% | −1.94 | |
| M01 | Persons | Named Groups | 47.3% | 49.9% | −2.57 | |
| E02 | Therapeutics | Techniques and Equipment | 34.7% | 37.4% | −2.69 | |
| D27 | Chemical Actions and Uses | Chemicals and Drugs | 37.3% | 41.0% | −3.65 |
Shares are of the month's papers that carry MeSH at all. Up to Mar 2026 the months were collected in bulk, after indexing; from Apr 2026 (the dashed line) they are collected daily, before much of it, with fewer headings per paper and a different mix of papers, so a category can step at that month without any change in the research. "Change" compares the average share over Sep 2025 – Aug 2026 with Sep 2024 – Aug 2025 in percentage points, leaving out the month still being collected; it is colored at 0.5 points or more, and until a full year has been collected daily it straddles the change in collection.