Formulation and analysis
Last updated: April 15, 2025
Rehabilitation is a problem-solving process. The first stage in any problem-solving process is to understand the problem in detail: what is the fundamental difficulty, which may or may not be the same as the initially identified problem; what are the critical factors related to the genesis and/or maintenance of the problem; what will happen if we take no action; what factors if any might help identify measures that could improve the situation; and what factors help decide which activities should be undertaken and/or should not be undertaken? The detailed analysis of a person’s difficulties leads to a formulation which combines a description and an explanation. The term is widely used in psychiatry and psychology but not in rehabilitation. The formulation is the vital bridge to the next section, rehabilitation planning and interventions, which uses information about prognosis and information to influence decisions between options. I have discussed how to increase competence in formulation in the syllabus; this page gives more background information.
Table of Contents
Introduction
“Ask not what disease the person has, but rather what person the disease has.”
William Osler (1849-1919)
“The psychiatric formulation is the clinician’s compass guiding treatment. It should accurately reflect the patient and his or her pattern of functioning as well as the precipitants, predisposing and perpetuating factors, and prognosis, while also being clear, concise and clinically useful.”
Len Sperry 1992 (here).
The psychiatric formulation is an important and necessary skill for all psychiatry residents. Thorough understanding of the formulation helps residents understand a patient’s unique psychopathology, organize a differential diagnosis, and prepare a useful treatment plan.”
These quotations provide a helpful description of the formulation and its potential benefits. Before discussing it in more detail, I wish to add another benefit: it helps overcome a cognitive bias often referred to as the Law of the Instrument.
This law was enunciated by Abraham Kaplan (1964) and, at the same time (1966), by Abraham Maslow, both psychologists, but it had been recognised for at least a century before. In 1868, the London Periodical published this: “Give a boy a hammer and chisel; show him how to use them; at once he begins to hack the doorposts, to take off the corners of shutter and window frames, until you teach him a better use for them, and how to keep his activity within bounds.”
Healthcare professionals seem especially prone to this bias. Formulating within a team setting may encourage professionals to recognise that their therapy may be less valuable than they think. More importantly, it may help the rehabilitation team acknowledge that their contribution is smaller than they imagine. As Maslow’s motivational needs show, people want more than just performing an activity.
Although Len Sperry (quoted above) considers the formulation, a more accurate metaphor is a map; the patient, not the formulation, is the compass that guides treatment. The formulation shows how a person arrived at the present location and the routes available to different destinations. It also shows obstacles, possible resources, and alternative routes to the same place., eat or refuel, etc.
Why is formulation needed?
Many people may feel that formulating is a waste of time. I suggest that failing to formulate wastes more resources. Continuing with the map metaphor, most people have taken the obvious road when driving, only to discover it was wrong. Although occasionally spectacularly incorrect, Google Maps and similar apps are widely used because they provide an effective route. The formulation provides the best map available; the patient chooses the destination.
Formulating requires considering alternative explanations for the situation and alternative ways forward. It enforces a pause, much like the team’s WHO surgical check before starting an operation. When undertaken by a team, the process exposes each member’s assumptions, reinforcing the need for a formulation.
The traditional biomedical diagnostic process uses a formulation variant when it requires a differential diagnosis. The professional should run through possible alternative diagnoses; they may discount them for lack of evidence, but often, the differential leads to further diagnostic tests, reducing the risk of starting an incorrect treatment.
As I write this, I realise how odd it is that the formulation process for making a medical diagnosis is weak, yet rehabilitation seems to have none. This is odd because biomedical diagnostic problems are closed, with only one correct answer. In contrast, rehabilitation problems are open, needing to consider the influence of many factors and how they interact. There is much more scope for a fundamental misunderstanding in rehabilitation.
The most considerable risk arises from the question many professionals ask themselves: “What can I do for this patient?” rather than “What does this patient need, and how can I help?” The former runs straight into the Law of the Instrument; we only explore what we can do and may even offer something we are unsure about because we can, rather than considering what would help the patient.
An insufficient formulation that fails to identify effective options or, equally seriously, identifies ineffective or less effective interventions than available alternatives will prolong the patient’s time improving and may fail to achieve the best outcome. A second serious but overlooked adverse effect is that others assume that the rehabilitation service has considered everything and will not consider further assessment and intervention.
Having said all that, I accept rehabilitation problems are straightforward, and one is tempted to take the obvious action. While a more detailed formulation may be unnecessary, a brief inquiry on contextual matters is wise. I would recommend always asking the person some contextual questions, such as:
- why did they seek help (i.e. what benefit did they expect)?
- Why have they come now rather than earlier?
- Why do they want this intervention rather than a plausible alternative (or doing nothing)?
These questions may alert you to other matters to consider before acting.
What is a formulation?
Formulation is the bridge between collecting information and planning; it is the crucial link between assessment and rehabilitation planning. This stage is essential in all problem-solving. In an article titled, The Process of Solving Complex Problems, Andreas Fischer and colleagues refer to “model buildings” and the need to develop “an internal representation of the problem”, constructing “a parsimonious but viable internal representation” of the situation.
Developing a formulation is sometimes referred to as formulation (or formulating). In more explicit terms, the person or team analyses the available data to build a framework or model that encompasses all the main features and explains how the problem arose. The process will inevitably also segue into planning what to do, but that is beyond the formulation itself.
The formulation summarising your understanding and describing a patient’s situation is the end product of the assessment and analysis. It is the explicit, formal exposition of the patient’s situation, setting out:
- what the presenting problem is, and
- what other problems there are;
- what the present position is in terms of:
- pathology, impairments, activities, social roles
- contextual factors, including the history (temporal context)
- analysing the causes of these problems and
- the factors exacerbating or maintaining the difficulties;
- what the prognosis is and
- what actions might help in resolving the issue.
- what the patient’s over-arching goal and interests are, and
- the availability of resources to help.
A complete analysis of a patient’s situation is critical in rehabilitation because it determines all subsequent plans and actions. To achieve a dependable understanding, you must collect all necessary data and use it to analyse and fully understand the patient’s situation.
The MindMap below shows how formulation fits into the broader problem-solving process in rehabilitation.
Formulation in psychiatry and rehabilitation.
Despite its importance, formulation is rarely mentioned in the rehabilitation literature. PubMed and Google Scholar searches reveal papers about psychiatric rehabilitation, but they do not specifically connect formulation to rehabilitation.
I found one paper discussing vocational rehabilitation after a stroke. Kate Radford et al wrote, “ … a focus of our intervention is to encourage collaborative working between OTs and CPs and development of a joint formulation (ie, structured approach to explore in detail an individual’s situation, and understand factors affecting their mood, functioning and so on to develop a tailored intervention); …” They also mention using “formulation to address complex cases”.
Consequently, we must draw on the rehabilitation literature, which should be fully applicable. Rehabilitation and psychiatry both use the holistic biopsychosocial model of illness as their analytic framework, and both specialities manage patients with complex problems involving many interacting factors.
Formulation and analysis
The drawing below illustrates how assessment and formulation are steps along the problem-solving pathway.
There are many articles and websites on undertaking formulation within psychiatry, and within most, there is a reference to “The X Ps”, where X is any number between 3 and seven. (for example, here or here). The letter ‘p’ may stand for:
- presenting problem
- pattern (of symptoms, I assume)
- predisposing factors
- precipitating factors
- perpetuating (maintaining) factors
- protective factors
- prognosis
- plan
The meanings attached to the letter p have grown like Topsy, just as the meaning attached to each letter of SMART, the widely used acronym in goal setting, has grown. (Over 113 different words for SMART; see here)
One approach (e.g. here) is to construct a table with the chosen ‘p’ words on the left-hand side, identifying the rows, and (in psychiatry) three columns for biological, psychological, and social factors. Some tables also include prompts or items that you can circle or highlight if present. This devalues the process because it removes most thinking and analysis.
There are many other approaches used in clinical reasoning (see here). From a formulation perspective, the most crucial consideration is that the clinician has a comprehensive description that does not omit important information. Whatever method you use, it is unlikely to be helped by trying to fill in a table while engaged in the diagnostic process of reaching a formulation.
On the other hand, the ideas or implicit questions that lead to the construction of a table may help in two ways. They may suggest hypotheses that you had not already thought of. They will also help organise and record the information collected.
Each clinician will develop and use their approach to collecting and analysing data; other methods are discussed elsewhere on this website (here and here). The clinician must consider each domain of the biopsychosocial model during assessment and when constructing the completed analysis.
The MindMap below illustrates an analytic approach to formulating and generating a rehabilitation plan.
Recording the information
The formulation and analysis are the bedrock on which all plans are built. Team members must understand the reasoning behind their planned activities because no one should act simply on the orders of another person, however senior or experienced. Therefore, it is essential to have an open team discussion leading to a record of the team’s formulation. The need to provide a reasonable justification for actions extends to the patient and family; they must have an accurate description given to them to understand their roles.
Many vital consequences flow from the proper written and accessible formal recording.
Commitment
In rehabilitation, coming to a diagnostic conclusion and making a firm decision is difficult because there are many unknowns and uncertainties. One common way to handle this is to speak in relatively vague generalities without committing to any specific formulation. The clinician can then adapt their understanding later without acknowledging that the original analysis was incorrect.
Unfortunately, this lack of commitment means the clinician learns less because they never have to acknowledge that a formulation was incorrect. Failures are often associated with good learning and improved quality of practice.
Conversely, committing to something in writing will make the clinician (or the clinical team) more careful and thoughtful. For example, the clinician may double-check the quality of a crucial piece of important information or ensure that information from all domains of the biopsychosocial model has been considered.
Facts and reasoning.
One significant difficulty when reviewing rehabilitation records is knowing the situation. The nature of the goals gives clues—if a goal is to walk further, it implies that the patient is walking—and incidental comments may provide other clues, but base facts are often not recorded. The reason is simple: Everyone involved at the time knows the situation and considers it unnecessary to record this information.
Another area for improvement is understanding why someone took specific actions or set certain goals while omitting other activities or plans. Interventions, even those that carry significant risk or use substantial resources, are rarely explicitly justified. This is crucial when asked to investigate an incident, and helpful when reviewing a patient one year later.
The increasing fragmentation of care, with staff rotas and moves reducing familiarity with patients, can only be ameliorated by better formal documentation of the formulation used and how it justified a decision.
Clinical continuity.
Most patients have long-term problems, and over a few months, many changes in team composition will often occur. Responsibility will pass from person to person, from team to team, and from organisation to organisation. A well-written formulation will reduce the risk of harm to the patient and make it more likely that a consistent approach is taken across settings and over time.
It may also reduce family stress. A formulation I prepared on a complex case was used for about 10 years with many service providers, saving the family from having to repeat a complicated and prolonged history at each consultation.
Understanding and trust
When patients and families have a situation explained, they usually forget most of it and misinterpret the remainder. That is entirely normal. Furthermore, clinicians giving information tend to be over-optimistic and leave out negative information. Probably mistakenly, clinicians feel patients do not want the whole truth.
Sharing the team’s formulation with the patient and family should increase understanding and trust. They will have much greater confidence in the information and follow advice with less questioning.
Thirdly, sometimes, the patient or family will point out errors in the formulation, perhaps disclosing new information or reminding the clinical team about the information given. I have shared all letters written about patients with them since about 1995 with no significant problems. Patients or families have noticed many minor and a few significant errors and added new information. This benefits the patient and ensures I am careful.
The formulation format is a matter for the team to decide. Nonetheless, it is unlikely to be helpful if it is just a table, uses jargon or abbreviations, or is handwritten and less legible.
The formulation must be well-written, using plain English (translated, if necessary, in equally straightforward terms), and with a clear, logical structure. It also needs to be succinct. A formulation that is more than one page is usually too long, and many suitable formulations will be much less. In more challenging cases, one may have a concise formulation with a more extended discussion of some aspects recorded separately.
Seeking feedback from patients and others will improve the recording of formulations.
Conclusion
Everyone will have an initial impression of the patient’s situation as soon as they meet. It is their understanding of the case. However, internal explanatory beliefs are often incomplete, sometimes wrong, and not subject to critical evaluation.
Sound rehabilitation plans depend on a complete understanding of the situation; the term used here is a formulation. This formulation, in turn, depends upon an appropriate assessment and data-collection process. Consistently developing a formulation and then presenting and recording it will improve the quality of rehabilitation.
This page has outlined some of the characteristics of a suitable formulation. One analogy is to consider a formulation as a map. The map shows how and why a patient arrived at his current location, including places (events) passed through and difficulties overcome. In this analogy, the patient’s route is determined by the disabilities, which will limit the ways available. However, the map will show the patient’s possible routes to move on. Which course is taken will depend upon the patient’s preferred reachable destination.