Editing Medicine (section)

== Branches ==
[[File:Drawing by Marguerite Martyn of a visiting nurse with medicine and four babies, 1918.jpg|thumb|Drawing by [[Marguerite Martyn]] (1918) of a visiting nurse in St. Louis, Missouri, with medicine and babies]]
Working together as an [[interdisciplinary team]], many highly trained [[health profession]]als besides medical practitioners are involved in the delivery of modern health care. Examples include: [[nurse]]s, [[emergency medical technician]]s and [[paramedics]], laboratory scientists, [[pharmacists]], [[podiatry|podiatrists]], [[physiotherapists]], [[respiratory therapists]], [[speech therapy|speech therapists]], [[occupational therapy|occupational therapists]], radiographers, [[dietitian]]s, and [[bioengineering|bioengineers]], [[medical physics|medical physicists]], [[surgeons]], [[surgeon's assistant]], [[surgical technologist]].

The scope and sciences underpinning human medicine overlap many other fields. A patient admitted to the hospital is usually under the care of a specific team based on their main presenting problem, e.g., the cardiology team, who then may interact with other specialties, e.g., surgical, radiology, to help diagnose or treat the main problem or any subsequent complications/developments.

Physicians have many specializations and subspecializations into certain branches of medicine, which are listed below. There are variations from country to country regarding which specialties certain subspecialties are in.

The main branches of medicine are:
* Basic sciences of medicine; this is what every physician is educated in, and some return to in [[Biomedical research#Preclinical research|biomedical research]].
* [[Interdisciplinary sub-specialties of medicine|Interdisciplinary fields]], where different medical specialties are mixed to function in certain occasions.
* [[Medical specialties]]

=== Basic sciences ===
* ''[[Anatomy]]'' is the study of the physical structure of [[organism]]s. In contrast to ''macroscopic'' or ''gross anatomy'', ''cytology'' and ''histology'' are concerned with microscopic structures.
* ''[[Biochemistry]]'' is the study of the chemistry taking place in living organisms, especially the structure and function of their chemical components.
* ''[[Biomechanics]]'' is the study of the structure and function of biological systems by means of the methods of [[Mechanics]].
* ''[[Biophysics]]'' is an interdisciplinary science that uses the methods of [[physics]] and [[physical chemistry]] to study biological systems.
* ''[[Biostatistics]]'' is the application of statistics to biological fields in the broadest sense. A knowledge of biostatistics is essential in the planning, evaluation, and interpretation of medical research. It is also fundamental to [[epidemiology]] and evidence-based medicine.
* ''[[Cell biology|Cytology]]'' is the microscopic study of individual [[cell (biology)|cells]].
[[File:Albert Edelfelt - Louis Pasteur - 1885.jpg|thumb|''[[Louis Pasteur]]'', as portrayed in his laboratory, 1885 by [[Albert Edelfelt]]]]
[[File:Statue of Robert Koch in Berlin.jpg|thumb|Statue of [[Robert Koch]] in [[Berlin]]]]
* ''[[Embryology]]'' is the study of the early development of organisms.
* ''[[Endocrinology]]'' is the study of hormones and their effect throughout the body of animals.
* ''[[Epidemiology]]'' is the study of the demographics of disease processes, and includes, but is not limited to, the study of epidemics.
* ''[[Genetics]]'' is the study of genes, and their role in [[biological inheritance]].
* ''[[Gynecology]]'' is the study of female reproductive system.
* ''[[Histology]]'' is the study of the structures of [[biological tissue]]s by light [[microscopy]], [[Electron microscope|electron microscopy]] and [[immunohistochemistry]].
* ''[[Immunology]]'' is the study of the [[immune system]], which includes the innate and adaptive immune system in humans, for example.
* ''[[Lifestyle medicine]]'' is the study of the [[chronic conditions]], and how to prevent, treat and reverse them.
* ''[[Medical physics]]'' is the study of the applications of physics principles in medicine.
* ''[[Microbiology]]'' is the study of [[microorganism]]s, including [[protozoa]], [[bacterium|bacteria]], [[fungus|fungi]], and [[virus]]es.
* ''[[Molecular biology]]'' is the study of molecular underpinnings of the process of [[DNA replication|replication]], [[Transcription (genetics)|transcription]] and [[Translation (biology)|translation]] of the genetic material.
* ''[[Neuroscience]]'' includes those disciplines of science that are related to the study of the [[nervous system]]. A main focus of neuroscience is the [[biology]] and physiology of the human brain and [[spinal cord]]. Some related clinical specialties include [[neurology]], [[neurosurgery]] and [[psychiatry]].
* ''[[Nutrition science]]'' (theoretical focus) and ''[[dietetics]]'' (practical focus) is the study of the relationship of food and drink to health and disease, especially in determining an optimal diet. Medical nutrition therapy is done by dietitians and is prescribed for [[diabetes]], [[cardiovascular disease]]s, weight and eating [[mental illness|disorders]], allergies, [[malnutrition]], and [[neoplasia|neoplastic]] diseases.
* ''[[Pathology as a science]]'' is the study of disease{{snd}}the causes, course, progression and resolution thereof.
* ''[[Pharmacology]]'' is the study of drugs and their actions.
* ''[[Photobiology]]'' is the study of the interactions between [[non-ionizing radiation]] and living organisms.
* ''[[Physiology]]'' is the study of the normal functioning of the body and the underlying regulatory mechanisms.
* ''[[Radiobiology]]'' is the study of the interactions between [[ionizing radiation]] and living organisms.
* ''[[Toxicology]]'' is the study of hazardous effects of drugs and [[poison]]s.

=== Specialties ===
{{Main|Medical specialty}}{{Globalize section|date=February 2023|UK}}
In the broadest meaning of "medicine", there are many different specialties. In the UK, most specialities have their own body or college, which has its own entrance examination. These are collectively known as the Royal Colleges, although not all currently use the term "Royal". The development of a speciality is often driven by new technology (such as the development of effective anaesthetics) or ways of working (such as emergency departments); the new specialty leads to the formation of a unifying body of doctors and the prestige of administering their own examination.

Within medical circles, specialities usually fit into one of two broad categories: "Medicine" and "Surgery". "Medicine" refers to the practice of non-operative medicine, and most of its subspecialties require preliminary training in Internal Medicine. In the UK, this was traditionally evidenced by passing the examination for the Membership of the [[Royal College of Physicians]] (MRCP) or the equivalent college in Scotland or Ireland. "Surgery" refers to the practice of operative medicine, and most subspecialties in this area require preliminary training in General Surgery, which in the UK leads to membership of the [[Royal College of Surgeons of England]] (MRCS). At present, some specialties of medicine do not fit easily into either of these categories, such as radiology, pathology, or anesthesia. Most of these have branched from one or other of the two camps above; for example anaesthesia developed first as a [[Faculty (teaching staff)|faculty]] of the Royal College of Surgeons (for which MRCS/FRCS would have been required) before becoming the [[Royal College of Anaesthetists]] and membership of the college is attained by sitting for the examination of the Fellowship of the Royal College of Anesthetists (FRCA).

==== Surgical specialty ====
{{Main|Surgery}}
[[File:Surgeons at Work.jpg|thumb|Surgeons in an [[operating room]]]]
''Surgery'' is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate or treat a [[pathological]] condition such as disease or [[injury]], to help improve bodily function or appearance or to repair unwanted ruptured areas (for example, [[Perforated eardrum|a perforated ear drum]]). Surgeons must also manage pre-operative, post-operative, and potential surgical candidates on the hospital wards. In some centers, [[anesthesiology]] is part of the division of surgery (for historical and logistical reasons), although it is not a surgical discipline. Other medical specialties may employ surgical procedures, such as [[ophthalmology]] and [[dermatology]], but are not considered surgical sub-specialties per se.

Surgical training in the U.S. requires a minimum of five years of residency after medical school. Sub-specialties of surgery often require seven or more years. In addition, fellowships can last an additional one to three years. Because post-residency fellowships can be competitive, many trainees devote two additional years to research. Thus in some cases surgical training will not finish until more than a decade after medical school. Furthermore, surgical training can be very difficult and time-consuming.

Surgical subspecialties include those a physician may specialize in after undergoing general surgery residency training as well as several surgical fields with separate residency training. Surgical subspecialties that one may pursue following general surgery residency training: ''<ref>{{cite web |title=What are the surgical specialties? |url=https://www.facs.org/education/resources/medical-students/faq/specialties#:~:text=The%20American%20College%20of%20Surgeons,surgery%2C%20otorhinolaryngology%2C%20pediatric%20surgery%2C |url-status=live |archive-url=https://web.archive.org/web/20210122184813/https://www.facs.org/education/resources/medical-students/faq/specialties#:~:text=The%20American%20College%20of%20Surgeons,surgery%2C%20otorhinolaryngology%2C%20pediatric%20surgery%2C |archive-date=22 January 2021 |access-date=18 January 2021 |website=American College of Surgeons |language=en}}</ref>''
* [[Bariatric surgery]]
* [[Cardiac surgery|Cardiovascular surgery]] – may also be pursued through a separate cardiovascular surgery residency track
* [[Colorectal surgery]]
* [[Endocrine surgery]]
* [[General surgery]]
* [[Hand surgery]]
* Hepatico-Pancreatico-Biliary Surgery
* [[Minimally-invasive surgery|Minimally invasive surgery]]
* [[Pediatric surgery]]
* [[Plastic surgery]] – may also be pursued through a separate plastic surgery residency track
* Surgical critical care
* [[Surgical oncology]]
* [[Organ transplantation|Transplant surgery]]
* [[Trauma surgery]]
* [[Vascular surgery]] – may also be pursued through a separate vascular surgery residency track

Other surgical specialties within medicine with their own individual residency training:
* [[Dermatology]]
* [[Neurosurgery]]
* [[Ophthalmology]]
* [[Oral and maxillofacial surgery]]
* [[Orthopedic surgery]]
* [[Otorhinolaryngology]]
* [[Podiatry|Podiatric surgery]] – do not undergo medical school training, but rather separate training in podiatry school
* [[Urology]]

==== Internal medicine specialty ====
{{Main|Internal medicine}}
'''Internal medicine''' is the [[medical specialty]] dealing with the prevention, diagnosis, and treatment of adult diseases.<ref>{{cite book |last1=Culyer |first1=Anthony J. |title=The Dictionary of Health Economics, Third Edition |date=31 July 2014 |publisher=Edward Elgar Publishing |location=Chelthenham, UK |isbn=978-1-78100-199-8 |page=335 |url=https://books.google.com/books?id=LUcjBAAAQBAJ&pg=PA335 |access-date=18 January 2021 |language=en |archive-date=18 August 2021 |archive-url=https://web.archive.org/web/20210818030924/https://www.google.co.in/books/edition/The_Dictionary_of_Health_Economics_Third/LUcjBAAAQBAJ?hl=en&gbpv=1&dq=medical+specialty+dealing+with+the+prevention%2C+diagnosis%2C+and+treatment+of+adult+diseases&pg=PA335&printsec=frontcover |url-status=live }}</ref> According to some sources, an emphasis on internal structures is implied.<ref>{{DorlandsDict|five/000063883|internal medicine}}</ref> In North America, specialists in internal medicine are commonly called "internists". Elsewhere, especially in [[Commonwealth of Nations|Commonwealth]] nations, such specialists are often called [[physician]]s.<ref>{{cite book |vauthors=Fowler HW |title=A Dictionary of Modern English Usage (Wordsworth Collection) (Wordsworth Collection) |publisher=NTC/Contemporary Publishing Company |year=1994 |isbn=978-1-85326-318-7 |url-access=registration |url=https://archive.org/details/dictionaryofmo00fowl }}</ref> These terms, ''internist'' or ''physician'' (in the narrow sense, common outside North America), generally exclude practitioners of gynecology and obstetrics, pathology, psychiatry, and especially surgery and its subspecialities.

Because their patients are often seriously ill or require complex investigations, internists do much of their work in hospitals. Formerly, many internists were not subspecialized; such ''general physicians'' would see any complex nonsurgical problem; this style of practice has become much less common. In modern urban practice, most internists are subspecialists: that is, they generally limit their medical practice to problems of one organ system or to one particular area of medical knowledge. For example, [[gastroenterology|gastroenterologists]] and [[nephrology|nephrologists]] specialize respectively in diseases of the gut and the kidneys.<ref>{{cite web
|url=http://www.racp.edu.au/index.cfm?objectid=49EF1EB5-2A57-5487-D74DBAFBAE9143A3
|title=The Royal Australasian College of Physicians: What are Physicians?
|access-date=5 February 2008
|publisher=[[Royal Australasian College of Physicians]]
|archive-url=https://web.archive.org/web/20080306053048/http://www.racp.edu.au/index.cfm?objectid=49EF1EB5-2A57-5487-D74DBAFBAE9143A3
|archive-date=6 March 2008}}</ref>

In the Commonwealth of Nations and some other countries, specialist [[Pediatrics|pediatricians]] and [[Geriatrics|geriatricians]] are also described as ''specialist physicians'' (or internists) who have subspecialized by age of patient rather than by organ system. Elsewhere, especially in North America, general pediatrics is often a form of [[primary care physician|primary care]].

There are many subspecialities (or subdisciplines) of [[internal medicine]]:
{{refbegin|20em}}
:*''[[Angiology]]/Vascular Medicine''
:*''[[Bariatrics]]''
:*''[[Cardiology]]''
:*''[[Critical care medicine]]''
:*''[[Endocrinology]]''
:*''[[Gastroenterology]]''
:*''[[Geriatrics]]''
:*''[[Hematology]]''
:*''[[Hepatology]]''
:*''[[Infectious disease (medical specialty)|Infectious disease]]''
:*''[[Nephrology]]''
:*''[[Neurology]]''
:*''[[Oncology]]''
:*''[[Pediatrics]]''
:*''[[Pulmonology]]/Pneumology/Respirology/chest medicine''
:*''[[Rheumatology]]''
:*''[[Sports Medicine]]''{{refend}}

Training in internal medicine (as opposed to surgical training), varies considerably across the world: see the articles on ''[[medical education]]'' for more details. In North America, it requires at least three years of residency training after medical school, which can then be followed by a one- to three-year fellowship in the subspecialties listed above. In general, resident work hours in medicine are less than those in surgery, averaging about 60 hours per week in the US. This difference does not apply in the UK where all doctors are now required by law to work less than 48 hours per week on average.

==== Diagnostic specialties ====
* ''[[Clinical laboratory]] sciences'' are the clinical diagnostic services that apply laboratory techniques to diagnosis and management of patients. In the United States, these services are supervised by a pathologist. The personnel that work in these [[medical laboratory]] departments are technically trained staff who do not hold medical degrees, but who usually hold an undergraduate [[medical technology]] degree, who actually perform the [[medical test|tests]], [[assay]]s, and procedures needed for providing the specific services. Subspecialties include [[transfusion medicine]], [[cellular pathology]], [[clinical chemistry]], [[hematology]], [[clinical microbiology]] and [[clinical immunology]].
* ''[[Clinical neurophysiology]]'' is concerned with testing the physiology or function of the central and peripheral aspects of the nervous system. These kinds of tests can be divided into recordings of: (1) spontaneous or continuously running electrical activity, or (2) stimulus evoked responses. Subspecialties include [[electroencephalography]], [[electromyography]], [[evoked potential]], [[nerve conduction study]] and [[polysomnography]]. Sometimes these tests are performed by techs without a medical degree, but the interpretation of these tests is done by a medical professional.
* ''Diagnostic [[radiology]]'' is concerned with imaging of the body, e.g. by [[x-ray]]s, x-ray [[computed tomography]], [[ultrasonography]], and [[nuclear magnetic resonance]] [[tomography]]. Interventional radiologists can access areas in the body under imaging for an intervention or diagnostic sampling.
* ''[[Nuclear medicine]]'' is concerned with studying human organ systems by administering radiolabelled substances (radiopharmaceuticals) to the body, which can then be imaged outside the body by a [[gamma camera]] or a PET scanner. Each radiopharmaceutical consists of two parts: a tracer that is specific for the function under study (e.g., neurotransmitter pathway, metabolic pathway, blood flow, or other), and a radionuclide (usually either a gamma-emitter or a positron emitter). There is a degree of overlap between nuclear medicine and radiology, as evidenced by the emergence of combined devices such as the PET/CT scanner.
* ''[[Pathology as a medical specialty]]'' is the branch of medicine that deals with the study of diseases and the morphologic, physiologic changes produced by them. As a diagnostic specialty, pathology can be considered the basis of modern scientific medical knowledge and plays a large role in [[evidence-based medicine]]. Many modern molecular tests such as [[flow cytometry]], [[polymerase chain reaction]] (PCR), [[immunohistochemistry]], [[cytogenetics]], gene rearrangements studies and [[fluorescent in situ hybridization]] (FISH) fall within the territory of pathology.

==== Other major specialties ====
The following are some major medical specialties that do not directly fit into any of the above-mentioned groups:
* ''[[Anesthesiology]]'' (also known as ''anaesthetics''): concerned with the perioperative management of the surgical patient. The anesthesiologist's role during surgery is to prevent derangement in the vital organs' (i.e. brain, heart, kidneys) functions and postoperative pain. Outside of the operating room, the anesthesiology physician also serves the same function in the labor and delivery ward, and some are specialized in critical medicine.
* ''[[Emergency medicine]]'' is concerned with the diagnosis and treatment of acute or life-threatening conditions, including [[physical trauma|trauma]], surgical, medical, pediatric, and psychiatric emergencies.
* ''[[Family medicine]]'', ''[[family practice]]'', ''[[general practice]]'' or ''primary care'' is, in many countries, the first port-of-call for patients with non-emergency medical problems. Family physicians often provide services across a broad range of settings including office based practices, emergency department coverage, inpatient care, and nursing home care.
[[File:Changing lives for girls and women every week (12330467294).jpg|thumb|[[Gynecologist]] Michel Akotionga of [[Ouagadougou]], [[Burkina Faso]]]]
* ''[[Medical genetics]]'' is concerned with the diagnosis and management of hereditary disorders.
* ''[[Neurology]]'' is concerned with diseases of the nervous system. In the UK, neurology is a subspecialty of general medicine.
* ''[[Obstetrics]] and [[gynecology]]'' (often abbreviated as ''[[OB/GYN]]'' (American English) or ''Obs & Gynae'' (British English)) are concerned respectively with childbirth and the female reproductive and associated organs. [[Reproductive medicine]] and [[fertility medicine]] are generally practiced by gynecological specialists.
* ''[[Pediatrics]]'' (AE) or ''paediatrics'' (BE) is devoted to the care of infants, children, and adolescents. Like internal medicine, there are many pediatric subspecialties for specific age ranges, organ systems, disease classes, and sites of care delivery.
* ''[[Pharmaceutical medicine]]'' is the medical scientific discipline concerned with the discovery, development, evaluation, registration, monitoring and medical aspects of marketing of medicines for the benefit of patients and public health.
* ''[[Physical medicine and rehabilitation]]'' (or ''physiatry'') is concerned with functional improvement after injury, illness, or [[congenital disorder]]s.
* ''[[Podiatric medicine]]'' is the study of, diagnosis, and medical and surgical treatment of disorders of the foot, ankle, lower limb, hip and lower back.
* ''[[Preventive medicine]]'' is the branch of medicine concerned with preventing disease.
** ''[[Community health]]'' or ''[[public health]]'' is an aspect of health services concerned with threats to the overall health of a community based on [[population health]] analysis.
* ''[[Psychiatry]]'' is the branch of medicine concerned with the [[biopsychosocial|bio-psycho-social]] study of the [[etiology]], diagnosis, treatment and prevention of [[cognitive]], [[perceptual]], [[emotional]] and [[behavioral]] disorders. Related fields include [[psychotherapy]] and [[clinical psychology]].

===Interdisciplinary fields=== <!--Interdisciplinary sub-specialties of medicine redirects here-->
Some interdisciplinary sub-specialties of medicine include:
* ''[[Addiction medicine]]'' deals with the treatment of addiction.
* ''[[Aerospace medicine]]'' deals with medical problems related to flying and [[Human spaceflight|space travel]].
* ''[[Biomedical Engineering]]'' is a field dealing with the application of [[engineering]] principles to medical practice.
* ''[[Clinical pharmacology]]'' is concerned with how systems of [[therapeutics]] interact with patients.
* ''[[Conservation medicine]]'' studies the relationship between human and non-human animal health, and environmental conditions. Also known as ecological medicine, [[environmental medicine]], or [[medical geology]].
* ''[[Disaster medicine]]'' deals with medical aspects of emergency preparedness, disaster mitigation and management.
* ''[[Diving medicine]]'' (or [[hyperbaric medicine]]) is the prevention and treatment of diving-related problems.
* ''[[Evolutionary medicine]]'' is a perspective on medicine derived through applying [[evolution]]ary theory.
* ''[[Forensic medicine]]'' deals with medical questions in [[legal]] context, such as determination of the time and cause of death, type of weapon used to inflict trauma, reconstruction of the facial features using remains of deceased (skull) thus aiding identification.
* ''[[Gender-based medicine]]'' studies the biological and physiological differences between the human sexes and how that affects differences in disease.
* ''[[Health informatics]]'' is a relatively recent field that deal with the application of computers and [[information technology]] to medicine.
* ''[[Hospice and Palliative Medicine]]'' is a relatively modern branch of clinical medicine that deals with pain and symptom relief and emotional support in patients with [[terminal illness]]es including cancer and [[heart failure]].
* ''[[Hospital medicine]]'' is the general medical care of hospitalized patients. Physicians whose primary professional focus is hospital medicine are called [[hospitalist]]s in the United States and [[Canada]]. The term Most Responsible Physician (MRP) or attending physician is also used interchangeably to describe this role.
* ''[[Laser medicine]]'' involves the use of lasers in the diagnostics or treatment of various conditions.
* Many other [[health science]] fields, e.g. [[dietetics]]
* ''[[Medical ethics]]'' deals with [[ethic]]al and [[moral]] principles that apply values and judgments to the practice of medicine.
* ''[[Medical humanities]]'' includes the [[humanities]] ([[literature]], [[philosophy]], [[ethics]], history and religion), [[social science]] ([[anthropology]], [[cultural studies]], [[psychology]], [[sociology]]), and the arts ([[literature]], theater, film, and [[visual arts]]) and their application to [[medical education]] and practice.
* ''[[Nosokinetics]]'' is the science/subject of measuring and modelling the process of care in health and social care systems.
* ''[[Nosology]]'' is the classification of diseases for various purposes.
* ''[[Occupational medicine]]'' is the provision of health advice to organizations and individuals to ensure that the highest standards of health and safety at work can be achieved and maintained.
* ''[[Pain management]]'' (also called ''[[pain medicine]]'', or ''algiatry'') is the medical discipline concerned with the relief of pain.
* ''[[Pharmacogenomics]]'' is a form of ''individualized medicine''.
* ''[[Podiatry|Podiatric medicine]]'' is the study of, diagnosis, and medical treatment of disorders of the foot, ankle, lower limb, hip and lower back.
* ''[[Sexual medicine]]'' is concerned with diagnosing, assessing and treating all disorders related to sexuality.
* ''[[Sports medicine]]'' deals with the treatment and prevention and rehabilitation of sports/exercise injuries such as [[muscle spasm]]s, [[muscle tear]]s, injuries to ligaments (ligament tears or ruptures) and their repair in [[sportsperson|athletes]], [[amateur]] and [[professional]].
* ''[[Therapeutics]]'' is the field, more commonly referenced in earlier periods of history, of the various remedies that can be used to treat disease and promote health.<ref>{{cite web|url=https://www.britannica.com/eb/article-9106176?query=Therapeutics&ct= |title=therapeutics (medicine) |website=Britannica Online Encyclopedia |access-date=21 April 2012 |archive-url=https://web.archive.org/web/20071218085231/https://www.britannica.com/eb/article-9106176?query=Therapeutics&ct= |archive-date=18 December 2007 }}</ref>
* ''[[Travel medicine]]'' or ''emporiatrics'' deals with health problems of international travelers or travelers across highly different environments.
* ''[[Tropical medicine]]'' deals with the prevention and treatment of tropical diseases. It is studied separately in temperate climates where those diseases are quite unfamiliar to medical practitioners and their local clinical needs.
* ''[[Urgent care]]'' focuses on delivery of unscheduled, walk-in care outside of the hospital emergency department for injuries and illnesses that are not severe enough to require care in an emergency department. In some jurisdictions this function is combined with the emergency department.
* [[Veterinary medicine]]; [[veterinarians]] apply similar techniques as physicians to the care of non-human animals.
* ''[[Wilderness medicine (practice)|Wilderness medicine]]'' entails the practice of medicine in the wild, where conventional medical facilities may not be available.