It is a common perception that medical students learn by being taught. This isn't entirely true, and in some cases is merely a lie perpetuated by hospitals to ensure that the extra funding associated with teaching keeps on pouring in. In fact, medical students learn by 'clerking', a lengthy process that involves taking a detailed history from a patient and then, when they're starting to get particularly fed up, performing a rigorous examination of any body parts they're willing to let you touch. This entry deals with the history part of a full inpatient clerking.

Ever since doctors started getting sued for making mistakes, they have been forced to document absolutely everything in their patients' notes, and this practice extends to students. Fortunately, by doing so, the history and examination taken are extensive and thorough, thus making a diagnostic error less likely. While there are many variations, the common themes found in all good medical histories are:

• Demographics
• Presenting Complaint (PC)
• History of Presenting Complaint (HPC)
• Past Medical History (PMH)
• Drug History (DHx)
• Family History (FHx)
• Social History (SHx)
• Systemic Review (SR)

Demographics

This may seem obvious, but if you don't ask the patient their name, age, left/right handedness, occupation, marital status and ethnicity at the start of the interview, you probably never will. This can be especially embarrassing if you later discover that your patient's name is Napoleon.

Presenting Complaint

This is the headline news of the history and should consist of the most important symptom(s) the patient complained of along with their duration in hours, days, weeks etc¹. Thus, you might write 'PC: crushing chest pain of 3 hour's duration', but you wouldn't write 'PC: heart attack'. If there is more than one important symptom, write them in a numbered list.

History of Presenting Complaint

Having drawn out the vital points, it's now time to fill in all the details. Start with the first symptom from the presenting complaint and ask every relevant question about it, then do the same for every other symptom the patient has given you. The questions that need asking vary depending on the symptom, but the example of pain is common enough that it deserves to be dealt with here.

Pain requires the 'Socrates' sieve²:

• Site: where is the pain?
• Onset: when did it start?
• Character: what does it feel like?
• Radiation: does it spread anywhere?
• Associated symptoms: does anything else happen with it?
• Timing: is it continuous, or does it stop and start?
• Exacerbating/Aggravating factors: what makes it better or worse?
• Severity: how bad is it out of ten? Is it the worst pain ever - worse than childbirth?

There are many other symptoms, each with its own set of questions. However, when a person with a problem relating to their gut comes along, you should enquire about any other GI symptoms by running through the appropriate part of the systemic review (see below). This is a good way to ensure you don't miss anything.

Having got the meat of the HPC, it is a good idea to cover the risk factors for any disease you suspect the patient to have. For instance, a patient likely to have had a heart attack should be asked about their weight, diet, exercise regime, blood pressure, cholesterol levels, whether there is a family history of heart problems, and whether they have diabetes³. If the patient is elderly and has had a fall, the risk factors for falling should also be explored.

Finally, you should enquire about the patient's progress since admission, if you haven't already. This consists of three parts: any changes in the symptoms, any investigations performed, and any treatments the patient has been given. In elderly patients, any change in the ability to perform activities of daily living (ADLs) such as walking, washing, dressing, and feeding should also be enquired after.

Past Medical History

The best past medical histories are evidence based: each diagnosis the patient has been given is listed along with when it was made, and then the diagnosis is justified by a brief list of symptoms that the patient had at the time. Treatments should be listed for any active problems, and any surgery or interventions the patient has had should be noted along with any complications.

As well as any past and present diseases, especially those resulting in a hospital admission, the patient should be asked directly about MI (heart attack), jaundice, tuberculosis, hypertension (raised blood pressure), rheumatic fever, epilepsy, asthma, diabetes mellitus and stroke. The mnemonic for this is 'M J Threads'.

Drug History

Always start by asking whether the patient is allergic to any drug, food, or anything else, and make a point of asking about aspirin and penicillin allergies. It is also useful to ask about hay fever, eczema and asthma if you haven't already. If the patient is allergic to a drug or food, they should be asked what happened when they were last given it.

Having done this, you can then continue to ask the patient about the drugs they usually take and those which are being administered to them while they are in hospital. The route of administration and dosage should be noted along with the frequency with which the drug is taken. The following notations are used:

• g, mg - grams, milligrams.
• po, pv, pr - per os (by mouth), per vaginum (vaginally), per rectum (rectally).
• im, iv - intramuscularly, intravenously.
• s/c - subcutaneously.
• od, bd, tds, qds - one, two, three and four times per day.

Micrograms, international units, intrathecal/spinal injections and frequencies of less than once a day are all best written out in full, as abbreviation can lead to confusion.

It is a good idea to ask the patient if they are taking any over-the-counter drugs or herbal medications as these can also have a bearing on the diagnosis.

Family History

An enquiry should be made as to whether any of the patient's first-degree relatives (parents, grandparents, siblings, children) have had any major disease, or whether they are simply alive and well. In the case of dead relatives, the cause of death and age at the time should also be sought. A family history of disease relevant to the patient's own likely diagnosis is particularly useful.

Social History

The social history consists partly of accusing the patient of smoking like a chimney, drinking like a fish and taking a range of illicit substances, and so could hardly be described as being 'social'. Alcohol intake should be considered in units⁴, and the patient should be asked when they started and/or gave up smoking, with the amount being expressed in pack-years⁵. It is useful to ask the patient what it is they tend to drink, and whether they smoke filter cigarettes, roll-ups or a pipe.

The remainder of the social history is concerned with the patient's dwelling, who they live with/care for/are cared for by, whether they have stairs at home, and whether they have any home help or home care. The patient's ideas, concerns and expectations (ICE) can also be included in the social history, although there is the tendency just to scribble down that the patient is in a bad mood because of the hospital food.

Systemic Review

The systemic review is a phenomenon found predominantly in medical student clerkings, as it is used to ensure that nothing has been missed. Each system of the body is considered in turn, with the following being asked about:

• Heart (CVS) - chest pain, shortness of breath (SOB), palpitations, ankle swelling, intermittent claudication⁶, orthopnoea⁷, paroxysmal nocturnal dyspnoea (PND)⁸, exercise tolerance, number of pillows slept on⁹.

• Lungs (RS) - cough (plus any recent change in a long-standing cough), sputum production, haemoptysis (coughing up blood), wheeze, stridor (a harsh, high pitched sound on inspiration), unusual snoring.

• Gut (GI) - weight loss/gain, change in appetite, dysphagia (difficulty swallowing), dyspepsia (heartburn), nausea, vomiting, haematemesis (vomiting blood), acid reflux, abdominal pain, constipation, diarrhoea, frequency of bowel opening, changes in bowel habit, appearance and smell of stools, blood/mucus/fat in stools, urgency, incontinence, tenesmus¹⁰.

• Urinary and Genital (GU) - Urinary: frequency (including frequency of urinating at night time), nocturia (needing to pee during the night), urgency, incontinence, difficulty starting, poor flow rate, terminal dribbling, polyuria (excessive amounts of urine), dysuria/pyuria (pain/burning), haematuria (blood in the urine). Genital: vaginal discharge, menstrual history (menarche/menopause), frequency and flow rate of menstruation, pain menstruating, first day of last menstrual period, pregnancy history.

• Neurological (CNS) - headache, changes in vision/hearing/smell/taste, fits, faints, funny turns, seizures, paraesthesia (numbness/tingling in fingers/toes), loss of feeling/movement, weakness, speech problems, psychiatric symptoms.

• Musculoskeletal - pain, stiffness or swelling of joints, morning stiffness, loss of muscle function.

• Endocrine - heat intolerance, cold intolerance, fatigue, sweating.

• Skin - rashes, dryness, lumps and bumps.

And Finally

The above is only a quick summary of the method used by medical students in the UK to take a history. Knowing which questions to ask requires a detailed knowledge of the possible diagnoses, and it is particularly telling that doctors are able to take histories a lot quicker than students who have just been released onto the wards. That knowledge is also required to make the diagnosis, which apparently can be made from the history alone in 90% of cases, with the remaining 10% requiring at least an examination as well. Whatever the case, a thorough examination should follow the history, either to confirm suspicions or to provide further clues as to what is wrong. One other important thing to mention is that a reasonable set of communication skills won't go amiss - being polite and tactful and treating the patient like a human being will certainly go a long way, but being able to understand the patient's feelings and empathise with them is a vital skill that all medical students must learn somewhere along the line.