"The exclusivity of medical knowledge and skill is being broken down. Inter-professional learning is now commonplace in medical education and seems likely to increase. Professional boundaries are being blurred as more and more things that were once the sole domain of doctors are being undertaken by other health care professionals. None of us works alone any longer, but in multidisciplinary teams in which we depend upon the expertise of others. This is not a diminution of medicine, but a strengthening of health care. We must acknowledge that, more than ever before, knowledge is available to patients and the public."
Sir Graeme Catto, Past-President of the UK General Medical Council (2005) 
Skills and competence in clinical decision-making are taught in various undergraduate healthcare programmes and cultivated through clinical experience. Many working diagnoses or clinical impressions, especially those for musculoskeletal (MSK) presentations, are developed through a process of exclusion, particularly when the context of diagnosis is uncertain. In other words, a definitive diagnosis may be elusive; however, a decision on management is still required.
Therefore, clinical decision-making centres on fundamental principles:
Avoiding patient harm (i.e., "Is it safe?"), and
Providing effective care (i.e., "Will it work?" and, "Are the necessary resources available?").
It should be noted at the outset that the challenge of reaching a meaningful diagnosis is by no means unique to chiropractors. Neuro-musculoskeletal presentations are notoriously difficult to diagnose precisely where labels (for MSK) are often arbitrary [2–4]. Terms such as 'wear and tear', 'degeneration', 'stress', 'arthritis', 'slipped disc', 'lumbago', 'cricked neck' and similarly ambiguous and vague terms are anecdotally still commonly encountered in practice.
Regarding low back pain, for example, the uncertainty was highlighted by the taxonomy subcommittee of the International Association for the Study of Pain (IASP) led by Bogduk (2000); "The only intellectually and clinically honest diagnosis for most cases of low back pain (is) lumbar spinal pain of unknown or uncertain origin ." (As an aside, it is debatable, in the opinion of the authors, whether this "intellectually and clinically honest" diagnosis adds superior clarity to that of the traditional chiropractic specific term "subluxation").
Initial decisions by chiropractors on management made on the basis of exclusion of 'red flags' constitute a defensive approach, particularly for non-specific spinal pain. As primary contact practitioners, chiropractors will invariably see patients with serious disorders yet to be diagnosed, such as emerging myocardial infarction, stroke, venous thrombo-embolism and aortic aneurysm, among others. In approximately 80% of these cases, the signs and symptoms of deterioration evolve over a few hours (sometimes days) or are episodic in nature, before obvious symptoms or complications occur . Yet, these clinical presentations are often either ignored, missed or a diagnosis delayed, potentially leading to a life-threatening situation due to late treatment . 'Red flags' may be implicated in as many as 1-5% of cases of spinal pain .
Competent clinical decision-making in chiropractic practice, therefore, not only revolves around common presentations, such as spinal pain or headache, but also covers the screening, examination, and potential triage of presentations that may necessitate referral to other healthcare providers. Differential diagnosis is part of this process of contemporary clinical decision-making expected of primary contact healthcare disciplines, of which formulating a diagnosis or clinical impression is a feature. Some chiropractors may view this approach taught in chiropractic undergraduate programmes as the 'medicalisation' of chiropractic, however, differential diagnosis is actually less about treating disease and more about the adoption of rational, clinical decision-making. By implication, the defensive approach to differential diagnosis alluded to earlier, where a definitive label is unlikely, offers a model for effective decision-making that is sensible, practical, and user-friendly and also congruent with traditional chiropractic practice.
Development of the 3-questions model
This paper explores the concept and elements of defensive problem-solving practice, with a view to developing a model of agile, pragmatic decision-making amenable to real-world application. A theoretical framework that reflects the elements of this approach and evaluation against obligatory standards of practice (Australia and the United Kingdom) will be offered in order to validate the potential of the 3-Questions Model.
The chiropractic profession, particularly in Western countries, finds itself in a rapidly evolving healthcare landscape, with 'modernisation' being a consequence of escalating costs, an aging population, and an ever-diminishing relative resource base . With a view to rationalising resources health system decision-makers are increasingly vigilant about the delivery of safe, evidence-based, cost-effective care, summarised as "the right care at the right time in the right place" [10, 11]. With this imperative in mind, the authors propose three straightforward questions that frame clinical decision-making within the context of diagnostic uncertainty.
Question 1: What is the likelihood I will delay access to more appropriate care for this patient?
Contemporary chiropractic offers an array of conservative treatments, selected and delivered on the basis of research evidence, tradition, expertise, patient preference, or a combination of all these. Yet, before any treatment can be applied, the practitioner has a duty of care to ensure that the patient will receive the most appropriate care at the right time, which may in fact necessitate referral to another healthcare provider. In other words, the preferences, traditions, and care philosophy of the practitioner are secondary to the needs of the patient, supported by the maxim; 'first do no harm' [12, 13]. In short, the practitioner must consider what has gone wrong with the patient as a whole to bring them to this point, and what role the chiropractor may play in their management .
The favourable natural history and episodic nature of uncomplicated spine-related disorders, the well documented 'Hawthorne Effect', combined with a low risk of adverse effects, may lull the chiropractor into a false belief that their favoured technique provides a panacea . Indeed, the belief that simply finding, quantifying and addressing 'subluxations' is the only role of the chiropractor ignores the reality that patients with serious or life threatening conditions can, and do, present to chiropractors. Also, over-confidence in their care philosophy and treatment technique may lead to the inappropriate treatment of specific patient populations. The failure to recognise these and consequently refer constitutes a significant proportion of malpractice litigation against chiropractors .
Chiropractors, along with all other health professionals, must be vigilant concerning the so called 'red flags' for serious illness, and be familiar with the signs and symptoms of emerging ill health or injury (13). Therefore, the practitioner must make several decisions on behalf of each patient on each visit. Firstly; whether the patient can be managed without collaboration with any other health practitioner, secondly; if the patient should be managed in conjunction with other healthcare provider(s), or thirdly; whether the patient should be rejected outright for chiropractic care.
It is relevant to note that various regulatory bodies expect inter-professional relationships to exist in the best interest of the patient, for example:
The Australian Code:
Good care is enhanced when there is mutual respect and clear communication between all health professionals involved in the care of the patient .
The UK code:
Identifying where it might be appropriate to consider co-managing the patient with another healthcare practitioner
Referring patients to other healthcare practitioners when their needs are beyond your own knowledge, skills and competence .
Question 2: Is my proposed treatment safe? (What is the likelihood of making this patient worse?)
The risk of adverse events with chiropractic care is enviably low. Even those sceptical of chiropractors and spinal manipulation admit that adverse side effects after chiropractic spinal manipulation are usually mild and transient [18, 19]. Combined with high levels of patient satisfaction, the low risk of manual and manipulative therapy reinforces the role of chiropractic in the management of spine-related disorders [20, 21]. Consequently, spinal manipulation is now recommended for consideration in recent guidelines for management of uncomplicated spinal pain .
Chiropractic practice embraces a broad clinical spectrum including manual, manipulative, soft-tissue, physiological and rehabilitative therapies - choosing which of these to apply, and when, have evolved over time as part of the so called 'Art of Chiropractic'. Based on the likely anatomical source of the presenting complaint, the chiropractor must advise the most appropriate clinical intervention, in the best interest of the patient .
Again, it is pertinent to note the requirements of regulators, whereby chiropractors must follow a patient-centred approach that minimises the risk of harm. Question 2 ensures compliance with the following sections:
The Australian code:
Section 2.2 Good care
Practising patient-centred care, including encouraging patients to take interest in, and responsibility for the management of their health and supporting them in this
Considering the balance of benefit and harm in all clinical management decisions .
The UK Code:
S2.6 Clinical decision making
When drawing up the working diagnosis or rationale for care, you must consider:
Relevant information about the natural history and prognosis of any complaint the patient has
The potential benefits and risks of care, including contraindications
The likelihood of recurrence or need for long-term management .
Question 3: Do I have all the information I need to answer the first two questions?
Cleland describes the concept of a 'treatment threshold', whereby the clinician gathers information from the health history and the physical examination and further tests until they decide whether or not to provide care for the patient . For the chiropractor, this is not as simple as checking they are breathing and have a spine! The health history and subsequently the relative value of findings from physical examination, orthopaedic tests, and available technologies are assessed according to sensitivity and specificity. Synthesis of the information gathered through history-taking, examination and evaluation of the patient is necessary to formulate a clinical impression, even if the diagnostic context is uncertain. Matters of safety, appropriateness, and cost-effectiveness of treatment are all paramount in the decision-making process and gathering information via thorough patient assessment permits the answering of the third question [23, 24].
The Australian Code:
Section 4.2 Good practice involves
A full and thorough assessment of patients using tools, tests and procedures that are appropriate for the gathering of information necessary to form a reasonable diagnosis .
The UK Code:
S2.6 Clinical decision making You must:
Evaluate the patient's health and health needs
Arrive at and document a working diagnosis or rationale for care, based on the evaluation of the information
Groopman (2007) advises patients to ask their doctor three pertinent questions which astute chiropractic practitioners would do well to ask themselves on behalf of their patient; "What else could it be?", "Is there anything that doesn't fit?" and "Is it possible there is more than one problem?" The patient may well in the chiropractors' opinion, have a biomechanical (functional) spinal lesion, but what else might they have [25, 26]?
Thus, the imperative of the clinical encounter is to ensure the patient is in the right place at the right time; more appropriate care is not likely to be delayed, the intervention is not likely to result in harm, and the clinician has enough information to decide. If the cause of the presentation can be labelled (diagnosed), are there co-morbidities, and if so are they significant? The context of the clinical decision is "what are the ramifications of being incorrect?" Notwithstanding the traditional chiropractic emphasis on specificity, the reality is the implications for the patient are greater if the clinician 'misses' serious illness or injury compared to making an incorrect MSK diagnosis.