| 1923 | Humans |
| 1884 | COVID-19 |
| 1549 | Pandemics |
| 1360 | SARS-CoV-2 |
| 1211 | Coronavirus Infections |
| 1208 | Pneumonia, Viral |
| 975 | Betacoronavirus |
| 760 | Female |
| 714 | Male |
| 565 | Adult |
| 497 | Quarantine |
| 480 | Middle Aged |
| 336 | Aged |
| 326 | Communicable Disease Control |
| 308 | Young Adult |
| 305 | Adolescent |
| 294 | Italy |
| 270 | Surveys and Questionnaires |
| 206 | Child |
| 198 | India |
| 184 | Cross-Sectional Studies |
| 152 | Social Isolation |
| 149 | Aged, 80 and over |
| 140 | Mental Health |
| 139 | Retrospective Studies |
| 125 | China |
| 117 | Anxiety |
| 113 | United Kingdom |
| 107 | Telemedicine |
| 105 | Child, Preschool |
| 93 | Spain |
| 93 | Physical Distancing |
| 93 | Air Pollution |
| 92 | Stress, Psychological |
| 88 | Emergency Service, Hospital |
| 87 | Depression |
| 83 | Public Health |
| 83 | Disease Outbreaks |
| 81 | Hospitalization |
| 81 | Environmental Monitoring |
| 80 | Infant |
| 79 | Time Factors |
| 79 | Incidence |
| 78 | Health Services Accessibility |
| 78 | Air Pollutants |
| 77 | Risk Factors |
| 76 | Infection Control |
| 76 | Cities |
| 74 | Particulate Matter |
| 71 | Exercise |
| 66 | France |
| 63 | COVID-19 Testing |
| 61 | Delivery of Health Care |
| 58 | Models, Theoretical |
| 57 | Prevalence |
| 56 | Health Policy |
| 55 | Socioeconomic Factors |
| 54 | Mental Disorders |
| 54 | Infant, Newborn |
| 54 | Adaptation, Psychological |
| 48 | Contact Tracing |
| 47 | Travel |
| 46 | Europe |
| 46 | Disease Transmission, Infectious |
| 46 | Age Factors |
| 45 | United States |
| 45 | Germany |
| 45 | Clinical Laboratory Techniques |
| 44 | Models, Statistical |
| 44 | Coronavirus |
| 43 | Health Personnel |
| 39 | Risk Assessment |
| 38 | Students |
| 37 | Basic Reproduction Number |
| 36 | Personal Protective Equipment |
| 36 | Forecasting |
| 36 | Feeding Behavior |
| 35 | Pregnancy |
| 35 | Life Style |
| 35 | Internet |
| 34 | Tertiary Care Centers |
| 34 | South Africa |
| 34 | Sleep |
| 34 | Sedentary Behavior |
| 34 | Longitudinal Studies |
| 34 | Global Health |
| 33 | Referral and Consultation |
| 33 | Patient Admission |
| 33 | Health Knowledge, Attitudes, Practice |
| 32 | Prospective Studies |
| 32 | Animals |
| 31 | Universities |
| 31 | Quality of Life |
| 29 | Social Media |
| 29 | Psychological Distress |
| 28 | Public Policy |
| 28 | Neoplasms |
| 28 | Emergencies |
| 28 | Diabetes Mellitus, Type 1 |
| 27 | Models, Biological |
| 27 | Diet |
| 27 | Cohort Studies |
| 26 | Sex Factors |
| 26 | Fear |
| 25 | Vulnerable Populations |
| 25 | Social Support |
| 25 | Loneliness |
| 25 | Follow-Up Studies |
| 25 | Education, Distance |
| 25 | Ambulatory Care |
| 24 | Parents |
| 24 | New Zealand |
| 24 | Health Services Needs and Demand |
| 24 | Computer Simulation |
| 23 | Mental Health Services |
| 23 | Blood Glucose |
| 22 | Mass Screening |
| 22 | Masks |
| 22 | Disease Management |
| 21 | Qualitative Research |
| 21 | Practice Guidelines as Topic |
| 21 | Health Behavior |
| 21 | Emotions |
| 21 | Elective Surgical Procedures |
| 21 | Comorbidity |
| 20 | Wounds and Injuries |
| 20 | Prognosis |
| 20 | Population Surveillance |
| 20 | Ophthalmology |
| 20 | Nepal |
| 20 | Epidemics |
| 19 | Treatment Outcome |
| 19 | Severity of Illness Index |
| 19 | Schools |
| 19 | Registries |
| 19 | Patient Acceptance of Health Care |
| 19 | Mortality |
| 19 | Blood Glucose Self-Monitoring |
| 19 | Algorithms |
| 18 | Time-to-Treatment |
| 18 | Social Behavior |
| 18 | Severe Acute Respiratory Syndrome |
| 18 | Resilience, Psychological |
| 18 | Remote Consultation |
| 18 | Poverty |
| 18 | Intensive Care Units |
| 18 | Hospitals |
| 18 | Health Surveys |
| 18 | Greece |
| 18 | England |
| 18 | Employment |
| 18 | Disaster Planning |
| 18 | Communication |
| 18 | Brazil |
| 18 | Age Distribution |
| 17 | Urban Population |
| 17 | Stroke |
| 17 | Self Report |
| 17 | Interpersonal Relations |
| 17 | HIV Infections |
| 17 | Government |
| 17 | Developing Countries |
| 17 | Caregivers |
| 16 | Videoconferencing |
| 16 | Societies, Medical |
| 16 | Sleep Initiation and Maintenance Disorders |
| 16 | Rural Population |
| 16 | Nitrogen Dioxide |
| 16 | Family Characteristics |
| 16 | Eye Diseases |
| 16 | Diabetes Mellitus, Type 2 |
| 15 | Triage |
| 15 | London |
| 15 | Hypoglycemic Agents |
| 15 | Family |
| 15 | Epidemiological Monitoring |
| 15 | Diabetes Mellitus |
| 15 | Australia |
| 15 | Asymptomatic Infections |
| 15 | Alcohol Drinking |
| 14 | Republic of Korea |
| 14 | Nigeria |
| 14 | Needs Assessment |
| 14 | Hospitals, University |
| 14 | Hospital Mortality |
| 14 | Health Status |
| 14 | Chronic Disease |
| 14 | COVID-19 Vaccines |
| 13 | Workload |
| 13 | Transients and Migrants |
| 13 | Switzerland |
| 13 | Sleep Wake Disorders |
| 13 | Real-Time Polymerase Chain Reaction |
| 13 | RNA, Viral |
| 13 | Patient Care |
| 13 | Pakistan |
| 13 | Ozone |
| 13 | Outcome Assessment, Health Care |
| 13 | Netherlands |
| 13 | Mobile Applications |
| 13 | Income |
| 13 | Food Supply |
| 13 | Emergency Medical Services |
| 13 | Disease Susceptibility |
| 13 | Cost of Illness |
| 13 | Bangladesh |
| 12 | Students, Medical |
| 12 | State Medicine |
| 12 | Singapore |
| 12 | ST Elevation Myocardial Infarction |
| 12 | Psychological Distance |
| 12 | Pregnancy Complications, Infectious |
| 12 | Poland |
| 12 | Occupational Health |
| 12 | Motivation |
| 12 | Israel |
| 12 | Insulin |
| 12 | Infectious Disease Transmission, Patient-to-Professional |
| 12 | Glycated Hemoglobin A |
| 12 | Decision Making |
| 12 | Case-Control Studies |
| 12 | Breast Neoplasms |
| 12 | Body Mass Index |
| 12 | Belgium |
| 12 | Anxiety Disorders |
| 11 | World Health Organization |
| 11 | Sex Distribution |
| 11 | Regression Analysis |
| 11 | Public Opinion |
| 11 | Protective Factors |
| 11 | Primary Health Care |
| 11 | Population Density |
| 11 | Patient Isolation |
| 11 | Length of Stay |
| 11 | Health Status Disparities |
| 11 | Health Resources |
| 11 | Health Care Surveys |
| 11 | Hand Disinfection |
| 11 | Facilities and Services Utilization |
| 11 | Cardiovascular Diseases |
| 11 | Attitude |
| 11 | Artificial Intelligence |
| 10 | Workplace |
| 10 | Weight Gain |
| 10 | Sweden |
| 10 | Substance-Related Disorders |
| 10 | Stress Disorders, Post-Traumatic |
| 10 | Reconstructive Surgical Procedures |
| 10 | Politics |
| 10 | Pilot Projects |
| 10 | Perception |
| 10 | Obesity |
| 10 | Nasopharynx |
| 10 | Japan |
| 10 | Interviews as Topic |
| 10 | Health Promotion |
| 10 | Guideline Adherence |
| 10 | Government Regulation |
| 10 | Geography |
| 10 | Genome, Viral |
| 10 | Epilepsy |
| 10 | Civil Defense |
| 10 | Chilblains |
| 10 | Austria |
| 10 | Antibodies, Viral |
| 10 | Ambulatory Care Facilities |
| 10 | Affect |
| 10 | Acute Disease |
| 9 | Viral Vaccines |
| 9 | Violence |
| 9 | Vehicle Emissions |
| 9 | Uncertainty |
| 9 | Turkey |
| 9 | Trauma Centers |
| 9 | Telephone |
| 9 | Surgical Procedures, Operative |
| 9 | Scotland |
| 9 | Polymerase Chain Reaction |
| 9 | Pediatrics |
| 9 | Patient Safety |
| 9 | Patient Compliance |
| 9 | Ophthalmologists |
| 9 | Logistic Models |
| 9 | Information Dissemination |
| 9 | Inflammatory Bowel Diseases |
| 9 | Glycemic Control |
| 9 | Dermatology |
| 9 | Dentists |
| 9 | Denmark |
| 9 | Continuity of Patient Care |
| 9 | Attitude to Health |
| 9 | Attitude of Health Personnel |
| 9 | Africa |
| 9 | Aerosols |
| 8 | Tomography, X-Ray Computed |
| 8 | Suicide |
| 8 | Social Networking |
| 8 | Sensitivity and Specificity |
| 8 | Screen Time |
| 8 | Saudi Arabia |
| 8 | Safety Management |
| 8 | Risk |
| 8 | Reverse Transcriptase Polymerase Chain Reaction |
| 8 | Public Health Surveillance |
| 8 | Public Health Administration |
| 8 | Program Evaluation |
| 8 | Percutaneous Coronary Intervention |
| 8 | Patient Satisfaction |
| 8 | Paris |
| 8 | Myocardial Infarction |
| 8 | Mothers |
| 8 | Mass Media |
| 8 | Malaysia |
| 8 | Interrupted Time Series Analysis |
| 8 | Internship and Residency |
| 8 | Hygiene |
| 8 | Human Activities |
| 8 | Housing |
| 8 | Hospitals, Pediatric |
| 8 | Health Education |
| 8 | Feasibility Studies |
| 8 | Databases, Factual |
| 8 | Cross Infection |
| 8 | Critical Care |
| 8 | Consensus |
| 8 | Cause of Death |
| 8 | Bayes Theorem |
| 8 | Appointments and Schedules |
| 8 | Alcoholism |
| 8 | Accidents, Traffic |
| 7 | Wales |
| 7 | Urologic Surgical Procedures |
| 7 | Unemployment |
| 7 | Thrombectomy |
| 7 | Survival Rate |
| 7 | Suicidal Ideation |
| 7 | Snacks |
| 7 | Smoking |
| 7 | Skin Neoplasms |
| 7 | Skin Diseases |
| 7 | Sexual Behavior |
| 7 | Seroepidemiologic Studies |
| 7 | Self-Management |
| 7 | Self Care |
| 7 | Search Engine |
| 7 | Residence Characteristics |
| 7 | Psychiatric Status Rating Scales |
| 7 | Professional Role |
| 7 | Practice Patterns, Physicians' |
| 7 | Portugal |
| 7 | Policy |
| 7 | Patient Selection |
| 7 | Patient Discharge |
| 7 | Outpatients |
| 7 | Neurosurgical Procedures |
| 7 | Mathematical Concepts |
| 7 | Heart Failure |
| 7 | Guidelines as Topic |
| 7 | Dementia |
| 7 | Delayed Diagnosis |
| 7 | Data Collection |
| 7 | Curriculum |
| 7 | Cell Phone |
| 7 | Biomedical Research |
| 7 | Asymptomatic Diseases |
| 6 | Waste Water |
| 6 | Symptom Assessment |
| 6 | Survival Analysis |
| 6 | Surgery Department, Hospital |
| 6 | Stochastic Processes |
| 6 | Social Stigma |
| 6 | Social Determinants of Health |
| 6 | Smartphone |
| 6 | Seasons |
| 6 | Risk Reduction Behavior |
| 6 | Risk Management |
| 6 | Resource Allocation |
| 6 | Research |
| 6 | Research Personnel |
| 6 | Research Design |
| 6 | Reproducibility of Results |
| 6 | Quality of Health Care |
| 6 | Psychotherapy |
| 6 | Psychosocial Support Systems |
| 6 | Protein Conformation |
| 6 | Phylogeny |
| 6 | Personnel Staffing and Scheduling |
| 6 | Personal Satisfaction |
| 6 | New York |
| 6 | Mutation |
| 6 | Mexico |
| 6 | Medical Oncology |
| 6 | Machine Learning |
| 6 | Liver Transplantation |
| 6 | Linear Models |
| 6 | Learning |
| 6 | Intimate Partner Violence |
| 6 | Internationality |
| 6 | Inpatients |
| 6 | Information Seeking Behavior |
| 6 | Immunoglobulin G |
| 6 | Heart Diseases |
| 6 | Feeding and Eating Disorders |
| 6 | Emergency Treatment |
| 6 | Education, Medical |
| 6 | Ecosystem |
| 6 | Economic Recession |
| 6 | Disease Progression |
| 6 | Disabled Persons |
| 6 | Commerce |
| 6 | Clinical Trials as Topic |
| 6 | Circadian Rhythm |
| 6 | Canada |
| 6 | Biopsy |
| 6 | Asia |
| 6 | Argentina |
| 6 | Appendicitis |
| 6 | Antiviral Agents |
| 6 | Adolescent Behavior |
| 6 | Acute Coronary Syndrome |
| 6 | Activities of Daily Living |
| 6 | Academic Medical Centers |
| 5 | Wounds, Gunshot |
| 5 | Work |
| 5 | Water |
| 5 | Water Quality |
| 5 | Waste Management |
| 5 | Viral Load |
| 5 | Video Games |
| 5 | Victoria |
| 5 | Urology |
| 5 | Uganda |
| 5 | Trust |
| 5 | Transportation |
| 5 | Thailand |
| 5 | Surgeons |
| 5 | Sulfur Dioxide |
| 5 | Substance Withdrawal Syndrome |
| 5 | Students, Nursing |
| 5 | Spike Glycoprotein, Coronavirus |
| 5 | Spatial Analysis |
| 5 | Social Control, Formal |
| 5 | Sexual Partners |
| 5 | Seizures |
| 5 | Security Measures |
| 5 | SARS Virus |
| 5 | Psychological Trauma |
| 5 | Prenatal Care |
| 5 | Pregnant Women |
| 5 | Postoperative Complications |
| 5 | Peptidyl-Dipeptidase A |
| 5 | Patients |
| 5 | Patient Health Questionnaire |
| 5 | Otolaryngology |
| 5 | Organizational Innovation |
| 5 | Occupational Exposure |
| 5 | Obsessive-Compulsive Disorder |
| 5 | Nutritional Status |
| 5 | Neurology |
| 5 | Monte Carlo Method |
| 5 | Monitoring, Physiologic |
| 5 | Molecular Dynamics Simulation |
| 5 | Melanoma |
| 5 | Medication Adherence |
| 5 | Leisure Activities |
| 5 | Jordan |
| 5 | Insulin Infusion Systems |
| 5 | Immunity, Herd |
| 5 | Hypoglycemia |
| 5 | Human Rights |
| 5 | Hospital Units |
| 5 | Hospital Departments |
| 5 | Hospital Bed Capacity |
| 5 | Hemorrhagic Fever, Ebola |
| 5 | Healthy Lifestyle |
| 5 | Healthcare Disparities |
| 5 | Health Communication |
| 5 | Health Care Rationing |
| 5 | Head and Neck Neoplasms |
| 5 | Hand Hygiene |
| 5 | General Surgery |
| 5 | Friends |
| 5 | Family Relations |
| 5 | Eye Banks |
| 5 | Environmental Exposure |
| 5 | Environment |
| 5 | Endoscopy |
| 5 | Educational Status |
| 5 | Domestic Violence |
| 5 | Disease Notification |
| 5 | Disasters |
| 5 | Diagnosis, Differential |
| 5 | Data Analysis |
| 5 | Cost-Benefit Analysis |
| 5 | Computer-Assisted Instruction |
| 5 | Computational Biology |
| 5 | Community Health Services |
| 5 | Clinical Competence |
| 5 | Child Welfare |
| 5 | Child Abuse |
