How Doctors Diagnose Illness! When you last visited the doctor you probably noticed that he or she started by asking some simple questions. Quite often this is enough for the experienced practitioner to get a good idea of what’s wrong with you and suggest appropriate treatment.
Sometimes things are more complicated of course and the doctor will want to carry out a physical examination and, if things are still in doubt, arrange for diagnostic testing, blood tests for example, to be carried out.
There has been a huge increase in highly technical diagnostic methods available to doctors: the growth of sophisticated imaging methods continues apace. However, the simple case history – which doctors have relied upon ever since there were doctors – usually provides ninety percent of the useful information, with physical examination and diagnostic tests used to confirm the diagnosis.
Presenting Complaint – Doctors Diagnose Illness
Case history taking usually follows a standardised logical sequence, starting with the history of the presenting complaint.
Pain is the reason most people visit the doctor. In addition to the site of the pain, the nature of the pain – sharp or dull – and what activities make the pain better or worse all help to determine the cause. For example: pain of musculoskeletal origin is normally affected by movement whereas pulsating pain might point to a circulatory cause.
If the presenting complaint is a cough it’s important to know if it is persistent or only occurs at certain times. A cough that is present all the time might point to a chest infection whereas a sporadic cough might be related to allergy.
Social History – Doctors Diagnose Illness
This covers a wide range of questions designed to provide some background to the patient and the complaint.
- Employment history: some occupations are associated with certain health risks. To name a few, animal workers are at risk from brucellosis, health workers from hepatitis B and miners from pneumoconiosis.
- Drug history: it’s clearly important to know what medication, whether prescription or over the counter, the patient is taking since medicinal drugs can be responsible for a wide range of symptoms. The adverse health effects of recreational drugs, alcohol and tobacco are well known so it’s essential to know if these might be contributing to or causing the patient’s condition. Incidentally doctors always assume that patients understate their alcohol consumption.
- Family history: some diseases have a well-proven genetic link, haemophilia for example. Others are known to run in families but the direct genetic link is less clear. The list of these conditions is large and includes: diabetes mellitus, osteoporosis, depression and some cancers. If your mother and father have diabetes, it doesn’t mean that you will get it but it does mean you are at increased risk, something that the doctor will need to take into account when trying to determine your condition.
This final part of the case history is really a screen, not aimed at the particular complaint but carried out to make sure nothing of importance has been missed.
Each system is taken in turn with the questions enquiring into the functioning of that system. Review of the cardiovascular system would include questions on chest pain and palpitations. That of the gastrointestinal system would include inquiry into loss of weight, bowel habit and indigestion.
This article is for information only. If you have any health concerns you should consult your doctor who will start by taking a case history.