In this part, you should explore in more depth the aetiology of the patient's illness.
You will need to draw on the precipitating, predisposing and perpetuating factors identified earlier in your summary to define the biological, psychological and social forces that have contributed towards a) the development of the patient's illness and b) their response to their illness.
A major difference between a summary and a formulation is that the latter seeks to link the pieces of information as opposed to listing them.
You should draw on relevant pieces of information from earlier parts of your report and consider the patient's presenting problem in the context of their history of chronic illness. You can also integrate evidence and concepts from the wider literature; however, your statements should be an understanding of the patient, not of the literature.
Lucy has a set of medical conditions, which can be summarised as Hereditary Endotheliopathy Retinopathy Neuropathy and Stroke (HERNS). The syndrome affects the endothelial vessels of the eyes and brain. Damage of the endothelium affects the biological functions of organs and leads to vascular disturbance and build-up of necrotic tissue. Lucy is also a lupus carrier - the antibody, lupus anticoagulant, is associated with arterial and venous thrombosis. Lucy also has high hypercholesterolemia, a genetic trait. Taking into account all of these biological factors, Lucy is predisposed towards developing a brain tumour. The fact that her father died of a stroke in his late 40s increases the likelihood that Lucy's signs and symptoms are genetically linked.
It is perfectly normal for healthy individuals to feel depressed when threatened with a diagnosis of cancer. However, Lucy's history of depression, 'fragile' personality, and poor coping mechanisms when faced with emotional problems make her more likely to be predisposed towards developing more serious forms of depression compared with otherwise healthy individuals.
Obviously, the diagnosis of a neural tumour may be directly linked to Lucy's recent onset of anxiety and depression. The co-current lack of stability in Lucy's life, including concern over the welfare of her son while she is ill and the loss of her job, may also be contributing towards her recent depressive symptoms. The timing of her illness is not especially good for Lucy, who is on the verge of committing herself to a secure relationship, by marrying and providing a 'family' for her son.
Lucy's experience of one illness after another has left her feeling insecure and with a sense of defeat, reflected in her personality. Lucy has a weak character in that she has poor frustration tolerance and coping mechanisms, causing her to emotionally collapse in stressful situations. Her weak personality is, therefore, a perpetuating factor contributing towards the worsening of her current condition.
Predisposing factors are the factors in the patient's history that make the patient susceptible or inclined toward presenting with, where applicable, an underlying diagnosis, and has "these symptoms" in this current situation.
Precipitating factors are the immediate factors or events that have caused the patient to present with or experience symptoms now. Depending on their backgrounds, life experiences, supports, coping strategies, and current circumstances, we might expect or even predict that two different people would react differently to the same (precipitating) event.
Perpetuating factors are the factors that are causing the patient's symptoms to continue or progressively worsen.
Some students find it helpful to use these headings in the formulation. Other students are able to write more freely without them. Note that most students appear to benefit from structuring the factual information in the history and mental state using headings.