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Physical examination

Generally speaking, diagnosis is the determination or determination of a disease . The word is derived from ancient Greek διάγνωσις diágnosis , German 'distinction' , 'decision' (consisting of διά- diá- , German ' through- ' and γνώσις gnósis , German 'knowledge' , 'judgment').

A diagnosis is made through a comprehensive overview and assessment of the findings . These can be, for example, individual complaints and symptoms ( symptoms ) or typical combinations of symptoms ( syndrome ). Normal findings or non-pathological deviations from the norm can also contribute to the diagnosis. These findings are collected through systematic questioning ( anamnesis ), through a physical examination, as well as through chemical or technical examinations. The diagnosis is crucial for the further course of treatment .

In medical classification systems , such as the International Classification of Diseases (ICD), diagnoses are schematically divided into groups and thus roughly mapped. Also in the psychology , the term diagnosis used (see Psychological Assessment ). In the nursing sector, a nursing diagnosis is a condition or health problem that justifies or influences nursing measures.

Paths to diagnosis

The path to diagnosis, the diagnosis, is also referred to as diagnostics and typically ends with the description of the clinical picture found. The names often include ideas about the cause and development of the disease ( etiology and pathogenesis ). The diagnosis can be made purely clinically (already fundamentally shown in the Hippocratic writings ). Mostly, however, it is a question of the specific sequence of various examinations, e.g. B. Psychological diagnostics or imaging diagnostics .

The term routine diagnostics can mean:

  • a measure that can be carried out without any special effort or additional requirements (e.g. in laboratories)
  • a sequence of measures carried out without specific suspicion (e.g. during screening, "check it out")
  • a measure to be carried out in treatment guidelines for clinical symptoms (e.g. posterior infarction)
  • a measure to be carried out in treatment protocols at fixed time intervals

Types of diagnoses

Ideally, the individual findings collected form a uniform picture and only allow a single, reliable diagnosis. However, reliable diagnoses cannot be worked out in all cases, which is why certain traditional terms have become established that refer to the degree of certainty of a diagnosis.

Exclusion diagnosis

The diagnosis of exclusion ( English diagnosis by exclusion is) a diagnosis, resulting from the gradual exclusion of all other possible diseases with the same symptoms result, until only the diagnosis of exclusion remains.

Suspicion and work diagnosis

If neither diagnostics nor differential diagnostics provide a reliable result, the suspected diagnosis will be given a V. a. (Suspicion of) prefixed. The terms suspected and work diagnosis are often used synonymously. They are basically the starting point for further investigations in order to substantiate or even reject a suspicion. In emergency medicine , the term work diagnosis is used for symptom complexes that can only be differentiated more closely in the context of emergency medical care or in an emergency room , because laboratory or other examinations, such as computer tomography or conventional X-ray diagnostics , require a corresponding amount of time. Examples of this are acute coronary syndrome and multiple trauma .

Reasons to limit yourself to justified suspicion, i.e. not to make an exact diagnosis, are typically that further examinations are not in a meaningful relationship to the therapeutic consequences, are rejected by the patient or pose a health risk for them. A lack of opportunities or time (for example in an emergency ) or cost reasons can also stand against this. For example, the diagnosis of flu infection is always a suspected diagnosis as long as no virological examination has been carried out. The term acute coronary syndrome has also become established in emergency medicine , under which ultimately all symptoms of poor blood flow to the heart are summarized. The differentiation as to whether it is specifically an angina pectoris or a heart attack then takes place in two stages.

Differential diagnosis

As a differential diagnosis (including differential diagnosis ; on finding letter abbreviated DD ) is defined as the total of all diagnoses that alternative explanation for the collected symptoms (symptoms) or medical findings must be taken into consideration or have been taken into consideration. A systematic differential diagnosis as a subject of nosology can be found for the first time in the writings of the Roman doctor Caelius Aurelianus in the 5th century.

Diagnosis ex juvantibus

If the diagnosis has not been established with certainty, a trial application of therapy based on an observed improvement in the clinical picture or a cure ex post can sometimes be used to conclude that an original diagnosis is correct. This is called Diagnosis ex juvantibus (diagnosis based on healing success).


An incorrectly made diagnosis is called a misdiagnosis. The causes can, for example, be due to incorrect applications in laboratory methods. A wrong diagnosis is often blamed on the doctors. In 2010, the medical profession's expert bodies found incorrect diagnoses or treatments in 2,199 patients, as a result of which 87 patients died. According to experts, the error rate is low in view of around 400 million doctor-patient contacts per year.

Procedure for developing a diagnosis (diagnostics)

A work diagnosis can be made at the first contact based on the medical history and physical examination. The latter is the starting point for the further procedure, with the aim of obtaining necessary, additional information. On the basis of the information that has been added, the working diagnosis is then confirmed, rejected or changed in the first step. Several such steps can sometimes be required to arrive at a reliable diagnosis.

The selection of the necessary diagnostic methods also depends on the likelihood, treatability and threat of the remaining differential diagnoses and the effort and risk associated with the measure. The process ends when only one diagnosis is possible. Often, however, the process is (sensibly) terminated beforehand - and then when the remaining differential diagnoses only contain entities that either

  • are not treatable,
  • are not in need of therapy or
  • all suggest the same (then often symptomatic) therapy.

A challenge in medical diagnostics is the lack of time in an emergency .

Basic diagnostics

The most important methods of diagnosis (finding a diagnosis) are the anamnesis (previous history, e.g. by interviewing the patient or other people in the environment), physical examination (examination of the patient using the senses and simple aids, especially through inspection , Palpation , percussion and auscultation ) as well as consideration of the patient's environment. For example, syringes or medication lying around at the location of an emergency or the condition of the patient's apartment can provide important information.

Apparatus diagnostics

In most cases, the simple examination methods are sufficiently precise to be able to identify or rule out diseases with life-threatening consequences. The use of apperative methods must be weighed up with regard to the expected benefit-risk ratio (e.g. in the case of stressful X-rays) and benefit-expense ratio (e.g. in cost-intensive MRI examinations). Apparatus diagnostics can be useful if it can be used to gain knowledge for the treatment of the patient. Exceptions to this are, for example, autopsies to clarify trade association or legal questions . Apparative diagnostics can also be helpful as part of the quality assurance of future treatments of others or when determining genetic causes of a disease in order to be able to treat relatives at an early stage .

Examples of apparatus diagnostics are laboratory diagnostics (examination of blood , urine , etc.), tissue and cell diagnostics using histology or cytology , imaging procedures ( sonography , endoscopy , X-ray , CT , MRT and nuclear medicine imaging), measurement of electrical fields of the body ( EKG , EEG , EMG and ENG ), functional tests ( lung function test , pressure measurements in vessels and sphincters ), reflex tests, provocation and stress tests (performance tests ( ergometry ) and glucose tolerance test ).

Diagnostic requirements

Whether a diagnosis is meaningful and expedient also depends on the quality of the definition of the underlying categories. A clinical picture can be assigned to a well-defined category (for example a broken bone in the forearm ) based on a few criteria (a history of falling, pain (see also: automated pain detection ), functional failure of the affected arm, discontinuity of the bone in the X-ray image) and thus an adequate therapy can be provided (e.g. plaster splint).

In the context of emergency medicine , it is important to gain knowledge about the first measures in a very short time. This is absolutely necessary , for example, in life-threatening situations such as a heart attack .

In the case of diseases whose categories are less clearly defined, controversial or complex, the risk of a misdiagnosis and thus of incorrect treatment is greater. This problem affects psychiatry , for example . Personality disorders in particular are problematic categories here.

Usually, the informative value of a diagnostic procedure must be able to withstand a review using scientific methods in order to be recognized by university medicine and health insurance . For example, not all diagnoses are paid for by the statutory health insurance companies in Germany. The evidence-based medicine has developed additional criteria to do so. Especially outside of hospitals and medical practices, methods are often used that do not meet the scientific criteria, for example in alternative medicine and naturopathy .


As part of the statutory accounting system ( G-DRG ), the ICD-10 (the international classification of diseases) must be used to encrypt diagnoses in Germany . The German Institute for Medical Documentation and Information (DIMDI) has published a German version for this, the ICD-10-GM  (German Modification).

The outpatient coding guidelines (AKR) were abolished by the GKV Supply Structure Act (GKV-VStG) on December 31, 2011.

See also

  • Triage , the initial assessment before the first diagnosis due to critical time pressure


  • Medical diagnostics in the past and present. Festschrift for Heinz Goerke on his sixtieth birthday. Edited by Christa Habrich , Frank Marguth and Jörn Henning Wolf with the assistance of Renate Wittern . Munich 1978 (= New Munich Contributions to the History of Medicine and Natural Sciences: Medizinhistorische Reihe , 7/8).
  • Rudolf Gross : Medical Diagnostics: Basics and Practice. Berlin / Heidelberg / New York 1969 (= Heidelberger Taschenbücher , 48).
  • Walter Siegenthaler : Differential diagnosis of internal diseases. 15th edition, Thieme Verlag , Stuttgart / New York 1984, ISBN 3-13-344815-3 .

Web links

Wiktionary: Diagnosis  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ^ Wilhelm Pape : Concise dictionary of the Greek language. Vol. 1: AK. Edited by Maximilian Sengebusch . 3. Edition. Vieweg & Sohn, Braunschweig 1914, p. 574; online at Zeno.org
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  5. Peter Reuter: Springer Lexicon Medicine. Springer, Berlin a. a. 2004, ISBN 3-540-20412-1 , p. 479.
  6. S. Grüne: Anamnesis - Examination - Diagnostics . Springer, 2007, ISBN 3-540-32866-1 , p. 28 ( limited preview in the Google book search).
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  9. ^ Wolfgang Wegner: Caelius Aurelianus. In: Werner E. Gerabek , Bernhard D. Haage, Gundolf Keil , Wolfgang Wegner (eds.): Enzyklopädie Medizingeschichte. De Gruyter, Berlin / New York 2005, ISBN 3-11-015714-4 , p. 227.
  10. Thousands of patients are victims of medical errors. fnp.de, June 21, 2011, archived from the original on September 13, 2016 ; accessed on October 11, 2019 .
  11. ^ H. Buchner et al .: Strategies for neurophysiological investigations. Electoneurography - Electromyography. Georg Thieme, 2011, ISBN 3-13-163151-1 , p. 4 ( limited preview in the Google book search).
  12. S. Grüne: Anamnesis - Examination - Diagnostics . Springer, 2007, ISBN 3-540-32866-1 , p. 205 ( limited preview in Google book search).
  13. ^ W. Golder: Use, costs and analysis in diagnostic radiology. Definitions and Glossary . In: Advances in X-rays and Imaging . tape 170 , no. 1 . Thieme, Stuttgart / New York 1999, p. 73-79 , doi : 10.1055 / s-2007-1011010 .
  14. ^ Jörgen Schmidt-Voigt: The outpatient cardiac examination. Basic cardiological diagnostics for the practice. Springer, Berlin 2011.
  15. ↑ Coding of diagnoses according to ICD-10-GM. Association of Statutory Health Insurance Physicians in Saxony, accessed on February 23, 2012 .