Should psychological formulation replace diagnosis for psychiatrists?

Should psychological formulation replace diagnosis for psychiatrists?

Summary

Psychological formulation has been promoted as a replacement for diagnosis in mental health. This does not take into account the time pressures facing psychiatrists and their needs in clinical practice. Using an example of a published psychological formulation for psychosis it can be demonstrated that psychological formulation is inferior to psychiatric diagnosis for clinical functions (prognosis and choosing treatments). It is also inferior for research (classifying participants) and social roles (including access to welfare and administrative integration with the rest of healthcare). For psychiatrists, diagnosis is still superior but should be supplemented by diagnostic formulation which can incorporate psychological mechanisms.

Declaration of Interest

The author has written a book awaiting publication which has large sections focussed on the value of diagnosis in mental health.

Introduction

Psychological formulation – sometimes called case formulation - has been promoted to replace diagnosis in clinical practice ^1,2 particularly to increase understanding of the patient and choosing appropriate interventions ².

Psychological formulation involves the organising of relevant clinical material to map out and summarise a patient’s problems – in collaboration with the patient over the course of clinical work - using psychological theories and knowledge to understand the patterns of difficulties and suggest ways forward to resolve these problems ^2,3,4.

Statements on the superiority of psychological formulation compared to diagnosis tend to be made on the assumption that the clinician works in a particular way – that they can spend a long time with relatively few patients, will see these patients many times with short intervals between sessions (for example weekly), often in non-urgent situations at civilised hours and that psychosocial interventions are the main therapeutic activity.

For their outpatient practice psychiatrists average 60 minutes for first appointments and 18 minutes for follow-up appointments⁵ (usually separated by weeks or months between appointments) carrying caseloads up to ten times of their colleagues⁶. Emergencies/ overnight and inpatient assessments are often similarly brief and patients may only be seen once or twice by the same doctor. This makes providing psychosocial interventions difficult and where effective medications are available these tend to be used as these are usually taken outside of the assessments thus making effective therapeutic interventions possible.  

This paper briefly discusses the usefulness of psychological formulation for psychiatrists in clinical, research and social functions.

Usefulness of psychological formulation for clinical practice

To evaluate the usefulness of psychological formulation for clinical functions an example of psychological formulation will be used to illustrate the points; the formulation used to understand ‘Dan’ and his psychosis in Section 7 of ‘Understanding Psychosis and Schizophrenia’⁷. This example is chosen for two reasons. Firstly, it is given as a good example of psychological formulation to enable understanding of psychosis by the Division of Clinical Psychology so has been given a stamp of approval by professionals whose core professional skills include psychological formulation⁴. Secondly, it is used for a case of psychosis and my main clinical work is with patients with schizophrenia and other related conditions, so this is an example I can relate to my clinical practice.

The ‘medical model’ relies on advising on and helping deliver interventions that improve health based on the best possible evidence⁸. For clinical practice, classification systems (such as diagnosis or psychological formulation) utility is judged on whether they allow communication of useful information between clinicians/patients/carers, accurate conceptions of the nature of the problem, provide information on prognosis (such as rates of relapse), aetiology/ causation, complications and which interventions to use and their chances of success^9,10,11,12. This utility is context-sensitive (such as limitations imposed on the way the professional works by resource demands including limited time)⁹. This information is probabilistic in nature rather than giving absolute certainty. Psychological formulation also aims to allow understanding of the patient and their situation^1,2,3,4.

Looking at the formulation of ‘Dan’⁷ it is about 150 words in boxes connected by of arrows linking past experiences, current events, thoughts, beliefs, responses and feelings. It certainly communicates information such as how these different aspects may be connected and lists important aetiological factors for psychosis such as adverse childhood experiences and substances.

The formulation plausibly links hypervigilance to childhood bullying (but ignoring that this hypervigilance would presumably be directed towards others and not his own body); somatic hypervigilance may lead to a belief that there is a lump in the neck but does not explain why the patient believes that this lump is transmitting thoughts. The lacunae in this formulation reflects the gaps in the evidence for purely psychological mechanisms linking adverse childhood experiences and psychotic symptoms content and nature¹³. It is possible the substance misuse is more closely linked to the generation of psychotic symptoms and the other factors such as childhood bullying are linked to the substance misuse rather than as depicted in the formulation.

The formulation provides some prognostic information such as substance use, childhood bullying and criminal activity being linked to worse outcomes such as higher relapse rates or aggression. The formulation provides useful pointers for psychotherapy such as addressing substance misuse or the links between past experiences, current life difficulties and thoughts and feelings.

On the other hand, this formulation has important information gaps. It is not clear how severe the psychotic symptoms are and whether they persist when substances are not being abused (such as psychosis related to substance intoxication or relatively brief psychotic episodes triggered by substance misuse) or whether the psychosis is caused by mood problems caused by adverse childhood experiences and/or current life difficulties – all these distinctions have clinical relevance not just for prognosis but for appropriate interventions and treatment¹⁴. For example, if the psychotic symptoms are only present during substance intoxication or for short periods afterwards then prolonged antipsychotic treatment is unlikely to be indicated.

In the text before the formulation of ‘Dan’ the diagnosis of schizophrenia is mentioned. This diagnosis is associated with a great deal of information such as factors associated with increased risk, associated differences in biological or psychological factors and the effectiveness of interventions¹⁵. Diagnostic constructs are associated with information that is learned by the clinician that allows easier recall and use of this information under time/ fatigue/ workload and other pressures in the context of brief appointments or emergency/ overnight working practices of most psychiatrists.

Schizophrenia as a diagnostic construct is defined by the absence of known organic factors explaining the clinical picture, nevertheless it is associated with multiple factors known to increase the risk of meeting the diagnostic criteria such as childhood adverse experiences and cannabis^16,17. Like many general medical conditions there is no single fixed outcome but we have evidence for a range of probable outcomes including recovery and their likelihood¹⁸. We also have evidence for the likely effectiveness of interventions in people meeting schizophrenia criteria such as antipsychotics¹⁹ and cognitive behavioural therapy for psychosis²⁰ to guide choice of therapeutic interventions.

An additional diagnosis – such as substance harmful use- will need to be used to indicate the important role of substance use affecting prognosis and to influence clinical management to include providing information on the effect of substances to the patient and referring for a psychosocial intervention to address the substance misuse. Two diagnostic constructs may thus need to be used but the total word count is still far less than that of the formulation. Although the diagnostic construct schizophrenia does not explicitly state the causative factors of this case many general medical diagnostic constructs - such as type 2 diabetes - do not state the causative factors in their title and even when a necessary cause is included in the title – such as tuberculosis – other important factors in the aetiology are not included in the title (for instance the role of overcrowded housing in tuberculosis)²¹. Psychosis is a very broad concept that some extend to unusual experiences that cause little harm or dysfunction to more severe states that can meet diagnostic criteria for schizophrenia or bipolar disorder²². It is therefore useful to identify a more specific classification than psychosis alone¹⁴ to provide more useful information to guide clinical decision making for the individual patient.

Research and Social Functions

Psychological formulation – except psychodynamic formulation - has disappointing reliability²³ impairing its usefulness in classifying participants in research. Conceptually as a classification system for research, psychological formulation would have to be reduce the emphasis on the individual-specific factors as they will vary a lot between individuals – they will need to focus on a few common elements otherwise the number of participants in each group would be too small and underpowered to detect statistically significant differences between groups. Although not suitable as a classification system for research, psychological formulation can be used as part of an intervention in studies evaluating their effectiveness.

There are many social functions of a health classification such as diagnosis – administrative (activity measurement and billing), organisational (services organised according to diagnosis or group of conditions), statistical (incidence/ prevalence and planning healthcare provision on basis of need) and access to benefits or special educational support²⁴. Given the high word count of psychological formulation, it’s highly individualised nature and the lack of horizontal integration with general medical diagnostic systems it is not very suitable as system for administrative, organisational, statistical or access to benefits or special educational support. Most health activity involves payment from third parties such as health insurance or government and providers are required to provide activity data to justify their expenditure – psychological formulation would not satisfy the requirements of third party funders as it would differ greatly between individuals making counting categories difficult. Similar problems apply for statistical and organisational purposes. Psychiatric diagnosis for all its faults is the most convenient system to fulfil administrative/statistical social functions²⁵.

To gain access to benefits for example, a diagnosis – with empirical evidence of association with impaired functioning and a recognised classified entity in ICD10 for instance – with additional description of impaired functioning in the individual is more likely to convince welfare agencies of eligibility for benefits – it relies on empirical evidence (lacking for psychological formulation in comparison to psychiatric diagnosis²)  and a standardised recognised classification not just expert assertion and is compatible with existing systems for general medical conditions.

Discussion

Psychological formulation is unable to replace psychiatric diagnosis for psychiatrists’ clinical work for the contexts in which they work – such as brief appointments or emergency/ night work – and requirements for empirical-based advice and decision-making⁸ as much of the evidence base is based on diagnostic classifications². This statement carries caveats. For those – including some psychiatrists – whose clinical work uses primarily psychosocial interventions in the context of long appointments with relatively few patients during routine hours may find psychological formulation more useful.  For some ‘organic’ conditions such as dementia or general medical conditions with psychological problems then psychological formulation will be used to address specific problems rather than overall management of the primary condition. Conversely for conditions where medication has little benefit – such as where people meet borderline personality disorder diagnostic criteria – then management plans would preferably be based on psychological formulation rather than diagnosis. This difference in clinical utility of psychological formulation depending on presenting condition illustrates the usefulness of psychiatric diagnosis – different conditions have different implications such as range of likely outcomes, treatment responses and usefulness of psychological formulation.

For the social functions of classification – such as administrative, statistical or access to benefits – diagnosis is superior to psychological formulation. Psychological formulation would not easily used as a classification system for participants in research making it harder to close the evidence gap with diagnostic based research. Diagnostic formulations – although disagreement exists as to what they should contain ^26,27 and can exclude or include psychological theories³ including incorporating psychological formulations from other professionals or their own work – can incorporate both the diagnosis (and differential diagnosis) as well as individual predisposing, precipitating, perpetuating and protective factors in the patient³.

For general medical conditions it is common practice to use additional information apart from the diagnosis to help with estimating prognosis and guiding clinical decision-making such as the use of staging for cancers, Glasgow Coma Scale for acute brain injury, DAS28 for rheumatoid arthritis and Modified Blatchford Score in acute upper gastrointestinal haemorrhage²¹.

Diagnostic formulation – beginning with a diagnosis then expanding with further relevant individual information and can include psychological theorising – is the best complex classification system for most psychiatrists in the context of the way they work and their need to provide evidence-based advice to the patient and to guide decision-making. It can build on the empirical information attached to a diagnosis with further individual and contextual factors (which may provide additional empirical evidence affecting prognosis or clinical management or aid further understanding of the patient and their predicament³). Diagnosis can also be combined with psychological formulation as they provide supplementary information.

References

1.  Division of Clinical Psychology. Classification of Behaviour and Experience in Relation to Functional Psychiatric Diagnoses: Time for a Paradigm Shift. DCP Position Statement. British Psychological Society 2013

2. Macneil, CA, Hasty, MK, Conus, P. and Berk, M. Is diagnosis enough to guide interventions in mental health? Using case formulation in clinical practice. BMC Medicine 2012; 10: p.111

3. Summers A., Boland B., Dave S., Gill H., Ingrams C. & Padakarra S. Occasional Paper 103: Using formulation in general psychiatric care: good practice. Royal College of Psychiatrists, 2017

4. Division of Clinical Psychology. Good Practice Guidelines on the use of psychological formulation. British Psychological Society 2011

5. Creed F. How consultants manage their time.  BJPsych Advances 1995; 1: 65-70

6. Tyrer P, Al Muderis O & Gulbrandsen G. Distribution of case-load in community mental health teams. 2001; Psychiatric Bull 25: 10-12

7. Cooke, A., Basset, T., Bentall, R., Boyle, M., Cupitt, C. and Dillon, J. Understanding psychosis and schizophrenia. British Psychological Society, 2014

8. Shah, P & Mountain, D. The medical model is dead--long live the medical model Br J of Psychiatry 2007; 191: 375-377

9. Kendell R.E. & Jablensky A. Distinguishing between validity and utility of psychiatric diagnoses. Am J Psychiatry 2003; 160: 4-12

10. Kendler KS. The Nosologic Validity of Paranoia (Simple Delusional Disorder).  Arch Gen Psychiatry 1980; 37: 699-706

11. First MB, Pincus HA, Levine JB, Williams JBW, Ustun B and Peele R. Clinical utility as a criterion for revising psychiatric diagnoses.  Am J Psychiatry 2004; 161: 946-954

12. Tennant N & Thompson IE. Causes and Logic in Epidemiological Psychiatry 2: Causal Models and Logical Inference. Br J Psychiatry 1980; 137: 579-582

13. Gibson, LE, Alloy, LB & Ellman, LM. Trauma and the psychosis spectrum: A review of symptom specificity and explanatory mechanisms Clin Psychol Rev 2016; B: 92-105

14. Frances A. A report card on the utility of psychiatric diagnosis. World Psychiatry 2016; 15: 32-3

15. Matheson, SL, Shepherd, AM & Carr, VJ. How much do we know about schizophrenia and how well do we know it? Evidence from the Schizophrenia Library Psychol Med 2014; 44: 3387-3405

16. Belbasis L, Köhler CA, Stefanis N, Stubbs B, van Os J, Vieta E, Seeman MV, Arango C, Carvalho AF, Evangelou E. Risk factors and peripheral biomarkers for schizophrenia spectrum disorders: an umbrella review of meta‐analyses. Acta Psychiatr Scand 2018 Feb;137: 88-97.

17. Radua J, Ramella‐Cravaro V, Ioannidis JP, Reichenberg A, Phiphopthatsanee N, Amir T, Yenn Thoo H, Oliver D, Davies C, Morgan C, McGuire P. What causes psychosis? An umbrella review of risk and protective factors. World Psychiatry 2018;17: 49-66

18. Menezes, NM, Arenovich, T & Zipursky, RB. A systematic review of longitudinal outcome studies of first-episode psychosis Psychol Med 2006; 36: 1349-1362

19. Leucht S, Leucht C, Huhn M, Chaimani A, Mavridis D, Helfer B, Samara M, Rabaioli M, Bächer S, Cipriani A & Geddes JR. Sixty years of placebo-controlled antipsychotic drug trials in acute schizophrenia: systematic review, Bayesian meta-analysis, and meta-regression of efficacy predictors. Am J Psychiatry 2017; 174:927-42

20. Jauhar S, McKenna PJ, Radua J, Fung E, Salvador R, Laws KR. Cognitive–behavioural therapy for the symptoms of schizophrenia: systematic review and meta-analysis with examination of potential bias. Br J of Psychiatry 2014; 204: 20-9

21. Walker BR, Colledge NR, Ralston SH & Penman I. Davidson’s Principles and Practice of Medicine (22nd Edition), Churchill Livingstone (Elsevier) 2014

22. Van Os, J & Reininghaus, U.  Psychosis as a transdiagnostic and extended phenotype in the general population World Psychiatry 2016; 15: 118-124

23. Flinn, L, Braham, L & Nair, R. How reliable are case formulations? A systematic literature review. Br J Clin Psychol 2015; 54: 266-290

24. Rose, N. What is Diagnosis For?  Lecture given at the Institute of Psychiatry (London) in 2013. Transcript can be found at http://nikolasrose.com/wp-content/uploads/2013/07/Rose-2013-What-is-diagnosis-for-IoP-revised-July-2013.pdf

25. Boyle M. The problem with diagnosis. The Psychologist 2007; 20: 290-292

Critique of Szasz The Myth of Mental Illness

This mini-essay will discuss the section “MENTAL ILLNESS AS A SIGN OF BRAIN DISEASE” only.

The paper can be found at http://psychclassics.yorku.ca/Szasz/myth.htm
(also at bottom of page)

I will argue that Szasz’s argument ignores that other models exist that do not assume mental illness is necessarily brain disease, that his arguments about differences between physical illness and mental illness are not accurate and he does not make the case that mental symptoms are epistemological errors.

Szasz begins the section by acknowledging that brain diseases can cause “disorders of thinking and behaviour” and correctly states that some believe that mental illnesses are all due to brain diseases. (This somatic school of thought was epitomised by Griesinger for whom all mental illnesses are brain diseases.) He then states “many” doctors (psychiatrists and physicians – perhaps meaning general and family medicine doctors) and scientists agree with this assertion. This is imprecise – does he mean almost all doctors and scientists or a bare majority or substantial minority? And which geographical grouping of doctors/ scientists – his colleagues, the US, the World? If Szasz is trying to prove mental illness is a myth he needs to establish this is the case for all conceptions of mental illness and if this somatic school is not a belief held by a majority of doctors/ scientists he cannot even argue he has proven mental illness is a myth spread by most doctors and scientists. Szasz also omits to mention the influential Jaspers whose “General Psychopathology” textbook was opposed to viewing all mental illness as brain disease. Depending on how influential Jaspers and those with similar viewpoints were depending on location and time, some doctors/ scientists may not hold the view that all mental illness is caused by brain disease. Since this model is ignored by Szasz he can only at best assert that he has demonstrated that mental illness is always brain disease is a myth as he has ignored other models.

Szasz states that the somatic school “implies” that “all problems in living” as an alternative to term for mental illness must be caused by changes in physical processes (amenable to scientific discovery) and not due to intrapsychic or social conflicts. He does not make the case that a broad conception of “problems in living” is believed by the somatic school is due to brain illness. What is encompassed by this broad term? Is it restricted to mental illness and what examples of mental illness is it restricted to? If it applies to mental illness – however so defined – then Szasz could make this argument for the somatic school - whilst ignoring mental illness models such as those of Jaspers and the biopsychosocial model. Biomedical models do accept the causative role of social factors via biological intermediaries. Szasz also does not state how and why the somatic school separates problems caused by intrapsychic/ social factors from mental illness.  Finally, “problems in living” seems a deeply inadequate descriptor for severe forms of mental illness for example someone starving themselves close to death for fear of fatness.

Szasz states that mental illness is viewed as identical to bodily disease but we know illness (of any type) does not correspond exactly to disease. Many medical illnesses – such as functional medical conditions -  do not have proven disease processes and some clear biological abnormalities are not regarded as illnesses such as benign glycosuria. Szasz then uses the term “mental and bodily diseases” so it is unclear if he is referring to all mental illness or just mental illness with or without proven brain disease.

Szasz next compares CNS symptoms to a rash or fracture but this is a category error- a rash would be more clearly categorised as a sign observed on examination and a fracture categorised as an investigation finding or diagnosis. Szasz claims CNS symptoms could not be “emotion or complex…behaviour” yet counter-examples exist – epilepsy or Alzheimer’s can cause these symptoms. Szasz claims beliefs cannot be a product of disease despite counter-examples including some he mentioned earlier associated with unusual beliefs such as GPI syphilis and delirium – even if we do not understand the mechanism of how these unusual beliefs are formed they seem likely as a product of these diseases. Even if we exclude examples or proven brain disease as not mental illness the precedent has been set and given our imperfect knowledge especially of mind/brain and the possibility of discovery in the future of disease processes the most that can be said is in “for mental illness in the absence of proven brain disease there are no established disease processes causing beliefs”.

Szasz asserts mental symptoms are an epistemological error by claiming mental symptoms are different from physical symptoms specifically pain but this is a category error – pain is at least in part a psychological experience involving the mind so is at least partly also a mental symptom and arguably since all symptoms are communications by patients, minds/brains are always involved. That we lack the ability to measure adequately physical counterparts of mental activity now does not mean we will not be able to in future – in the past we could not measure many bodily activities that are possible now.

Szasz asserts mental health symptoms are classified using psychosocial comparisons/ judgements but physical symptoms and signs are also compared to the doctor’s judgements e.g. of what heart sounds should sound like. Psychosocial factors including culture also affect what are thought of physical symptom expression e.g. pain. Given the importance of psychosocial factors affecting expression of mental outputs of speech and behaviour it is a strength, not a weakness,  that these are taken account of e.g. before a belief is classified as delusional it must be outside the patient’s cultural norms.

Szasz only addresses one model of mental illness – the somatic school – and by failing to address other models cannot prove mental illness is a myth. His arguments against the somatic school are weakened by counter-examples and category errors and false distinctions between physical and mental illness.

http://psychclassics.yorku.ca/Szasz/myth.htm

Diagnosis, uncertainty and the hub of clinical decision making

Is diagnosis an authoritative statement about a patient’s condition? Does it involve 100% certainty that this is the correct label for the type of the patient’s problems, what the underlying causes are for the problems, that this is the sole problem, what the correct treatment should be, what the outcome is going to be with and without treatment?

In fact a doctor’s diagnosis is a summary of a series of possibilities that trigger further enquiries, not least is the diagnosis correct and should it be changed. These possibilities inform the doctor’s management plan such as what types of further tests and examinations the healthcare team should do and when.  What are these possibilities?

• What kind of features does this diagnosis present with? The range of probabilities of how the diagnosis will present in terms of symptoms, signs, lab tests or other important clinical features. This will tell the doctor how to recognise the condition, what information to seek and how. It will guide the doctor in what questions to ask, how to interpret the answers, what tests to run and what pattern of results to look for. As noted elsewhere this is a pattern recognition exercise.
• What if the diagnosis is wrong? The possibility that the diagnosis is correct (or its’ reliability) according to some external criteria – usually for most medical specialties, a test (such as biochemical test, pathology of diseased organ, imaging test) but could also be another expert doctor’s opinion. This possibility of the diagnosis made being incorrect means the doctor should continue to be vigilant for disconfirmatory information i.e. information that suggests the diagnosis is incorrect. This may be symptoms or signs or laboratory tests or not responding to a treatment that usually works or other differences in the clinical picture that are usually incompatible with the diagnosis or better explained by another diagnosis. If these arise then the doctor should revise (change) the diagnosis to one that fits the information better. The doctor keeps a differential diagnosis (or many differential diagnoses, or even the “null option” of no diagnosis/ no illness) in mind. For example, a patient with initial diagnosis of alcohol intoxication but then the doctor notices they have signs of a subarachnoid haemorrhage and changes the diagnosis to that instead.
• What other illnesses could be present? The possibility that other healthcare problems are also present, known as co morbidity. Like birds of a feather, some illnesses are associated with other illnesses being present. An illness may increase the chances of developing another illness . Illnesses have similar underlying causes thus increasingly the probability of more than one illness. This alerts the doctor to look for signs or symptoms or run tests or investigations for these other potential diagnoses. For example if a patient has an unusual infection diagnosed such as pneumocystis carinii pneumonia this makes the doctor think that the patient may have an immunocompromised state (immune system that is very poor at fighting infections) so will run tests looking for causes of this such as HIV infection as well as taking precautions to reduce the chances of other infections.
• What complications should I look out for? Apart from what the doctor has recognized and identified there can be other problems or features known to be associated with the diagnosis. This triggers the doctor to look for these other potential problems through asking the patient for symptoms indicating the problem is present, examining the patient to look for these problems and running further tests to identify these problems. Even if the problems are not present at the initial assessment, they can develop later so armed with this knowledge the doctor can be alert for them developing through history taking, clinical examination and running tests in the future. For example if a patient is seen with a heart attack (myocardial infarction) there are a variety of complications the doctor will be aware of and monitor for such as heart failure or cardiac arrest.
• What treatment should I offer? The range of possibilities of treatment and the range of responses to treatment – what are the different alternatives of treatment (not just medication)/ help available, how likely the diagnosed condition will respond to treatment, how long this improvement will take, what are the signs of this improvement taking place and what side effects may occur with treatment and how to identify these. If the treatment fails and the diagnosis is correct what are the likely causes for treatment failure (e.g. maybe not taking the medication or not changing lifestyle factors) and how to identify them. Further treatment option knowledge is also triggered at this point. Notice how, as in the above examples, diagnosis links into other types of knowledge, in this case pharmacology and treatment guidelines. The doctor can discuss with the patient these important details and ask them what treatment choices they want to make. The doctor is reducing the information asymmetry deficit. For example if a patient presents with high blood pressure the doctor can discuss what the different options are e.g. lifestyle changes, medication and when to review them to see if succeeding or what changes in treatment are needed.
• What do I expect to happen in people with this diagnosis? The range of possibilities of outcomes seen with this diagnosis. Most illnesses don’t have a fixed outcome but have a range of probable outcomes. This allows the doctor to discuss these details with the patient. The range of factors that are associated with better and worse outcomes are also linked with the doctor’s knowledge about the diagnosis and allow the doctor to look for the presence of them and modify them if possible. For example, if a case of cancer is seen the doctor will try and identify the size of the tumour, whether it has spread (metastasised) including to local tissues or to lymph nodes or to other areas of the body. He will also look for other factors that may affect outcome such as socioeconomic class, other factors that can be modified e.g. if smoking worsens the outcome of the cancer that can be targeted with smoking cessation. For some tumours genetic testing of the tumour can take place to identify targeted treatments.

It can be seen that diagnosis is provisional and is always open to review as more information comes to light. It is the hub of linked information that the doctor has learned about the illness that guides the doctors management plan: what tests are run, what signs or symptoms are observed for, how to recognize if the diagnosis is wrong, what other illnesses may also be present, what treatment options are discussed and chosen, what to expect in terms of outcomes and what further information is sought to refine the outcome and improve it. Doctors learn about medicine by learning about a diagnosis and the interlinked information as described above. 

Diagnosis can be thought of as a quantum reflexive hyperlinked seed. Quantum reflects the uncertainties as to whether the diagnosis is right, outcome, treatment and so on. Reflexive in that the information associated with the diagnosis includes procedures to monitor whether it is accurate or, like the phoenix, be immolated to be replaced by a new diagnosis. Hyperlinked in that the diagnosis is a hub that links to multiple domains of information as described above. The seed describes the compact nature of a simple term like the diagnosis yet jam-packed with the information and procedures needed to grow a management plan to help the patient with the right environment of a doctor with the ability to respond and act on the information from the patient.

                

To boldly go….(where Anglophone psychiatrists rarely have been before)

 

I went to the EASE conference in Copenhagen for 3 days.

(EASE =Evaluation of Anomalous Self-Experience)

It was the best psychiatry conference I’ve ever been to.

The purpose of an EASE interview is to enquire about a whole range of unusual experiences called disorders of the self (or self-disorders) that were described initially in patients with schizophrenia (or dementia praecox) by German psychiatrists nearly 100 years ago that have been largely lost to Anglophone psychiatry .

The EASE was devised by Prof Parnas and collaborators such as Lennart Jansson, Paul Moller,  Peter Handest, Jorgen Thalbitzer, Dan Zahavi.

It’s based from a philosophical and phenomenological viewpoint. It uses terms like ipseity, hyper-reflectivity that I don’t trust myself to explain properly.

I strongly advise going to the website (which is in the process of being refreshed as of 12/11/14) www.easenet.dk with better descriptions and links to reading materials.

So what was so great?

·         Whole new world of patient experiences that were closed to me

·         The tradition of (European)  continental psychiatry

·         The implications of self-disorders clinically

Well it was refreshing and eye-opening to me to discover a whole world of unusual experiences that I was dimly aware of at best and unaware of usually. The correlation is of course that I didn’t ask my patients about these experiences. These experiences include feeling detached from the flow of time, from their own thoughts and bodies, from merging with external objects, from feeling an absence of their core being and more. 

The EASE interview (which usually takes place over several sessions and can be quite lengthy) helps you to ask about these experiences and categorise them. Prof Parnas strongly discourages a structured interview approach (he calls it “an atrocity”). He also cautions that “humility is essential” when categorising these existential experiences and for psychiatrists to avoid becoming “biological idiots”.

Germans wrote the great songs of psychiatry from the late 19^th to early-mid 20^th century. There are the German Psychiatry “Beatles” of Kraepelin, Kurt Schneider, Jaspers and Bleuler.

To modern Anglophone psychiatry, Bleuler was the Ringo Starr of this quartet.  In US-UK-Down Under eyes Kraepelin split the psychosis based on course, Schneider using First Rank Symptoms (used as the basis of “core schizophrenia”), Jaspers defined psychopathological terms and Bleuler just came up with the name “schizophrenia”. The reason for this is that Bleuler’s concept of schizophrenia (which included a lot of unusual experiences assessed in EASE) was overly expanded in the US to include a lot of cases of depression and personality disorders. This problem was highlighted in the US-UK diagnostic study and explained the very high rates of schizophrenia in the US particularly New York. The yanks then decided to standardise on the British version believing it to represent Schneider’s concept of schizophrenia. The Brits however had made an error of their own, they had too narrow a concept of Schneider. Kurt Schneider himself had described unusual experiences similar to Bleuler on a spectrum with First Rank Symptoms at the extreme end of the spectrum. This error was compounded by DSM treating First Rank Symptoms as delusions (e.g. of thought broadcasting) not as experiences.

Denmark for obvious geographic reasons is still influenced by the original German concepts untainted by Anglophone misconceptions. To me, it was fantastic to hear our Danish hosts switch fluently from perfect English to German and Danish in describing psychopathology.  There is still this strong tradition of Continental psychiatry paying close attention to the source materials.

 Bleuler stated that the delusions and hallucinations were secondary symptoms to the primary disturbances in autism, affect, associations and ambivalence. A lot of these disturbances are measured in the EASE scale which leads me into the third point, the clinical implications.

My viewpoint on the classification of psychosis has changed with experience and research. Initially I viewed schizophrenia and bipolar disorder as very separate illnesses. Over the past 10 years I’ve changed my conception of psychosis to a spectrum (like a rainbow) with schizophrenia and bipolar disorder as different colours on this spectrum at nearly opposite ends (like violet and red on a rainbow) – see my first blogpost “Utility without Validity”.

I may be at a tipping point of a change back to viewing them as more separate than before. This is because disorders of self are far commoner in schizophrenia than in bipolar disorder (see the papers on the EASE website, one paper said disorders of self were 9 times commoner in schizophrenia compared to bipolar disorder). There are similar amounts of disorders of self in schizophrenia and schizotypal disorder. This indicates that schizotypal disorder and schizophrenia lie on a spectrum.

A gradient of severity of disorders in self seems to exist

1.       Schizophrenia and schizotypal disorder

2.       Bipolar disorder/ other psychosis

3.       Other mental disorders

4.       No mental disorder

This would seem useful in identifying and separating schizophrenia from other mental disorders, the differentiation from schizotypal disorder being one of degree of positive and negative symptoms present. There was no relationship between self-disorder scale scores and borderline personality disorder symptom scores.

There were other clinical implications. One of them was that in a sample of patients thought to be at high risk of developing psychosis, it was the presence of disorders of self that predicted transition to psychosis best. The transition rates to psychosis in this at risk group is dropping to perhaps 20—25% in 2 years. If this finding is replicated this improves our ability to predict transition and avoid unnecessary treatment.

Disorders of self are not merely straight forward neuropsychological impairments by another name and didn’t correlate with neuropsychology scores.

For me the biggest implication is that if these disorders of self are the fundamental disorder of schizophrenia, the soil from which the other symptoms grow out of?

If so, what effect do antipsychotics have on this? I suspect they may dampen but not remove them. EASE assessments are done when the patients aren’t floridly psychotic yet they still seem to describe these problems as active. So current antipsychotics may do a good job on delusions and hallucinations (a far better job than e.g. CBT for psychosis or CBTp) but not on these disorders of self.

Further research would also be needed on how disorders of self effect prognosis and risk. In the meantime I am going to be using EASE interviews on a range of patients, some with schizophrenia, some with psychosis but unlikely to be schizophrenia and other patients without a psychosis.

There no CBT models of these type of problems and no apparent CBT interventions for them (indeed in the COMPARE CBTp trial high scores on the “disorganisation” item are an exclusion criteria from the trial and many disorders of the self do seem linked to hebephrenic type pictures and hence high scores on the “disorganisation” item).  

You could argue an existential problem like disorders of the self should respond to psychodynamic therapy but early experience of this in schizophrenia was discouraging. It has been modified recently to reduce paranoia induced by the therapy and perhaps this might be an avenue of approach. My hunch is these experiences are so dislocating that it might be a bit too hard for “the couch”.

So disorders of self could revolutionise how we conceive of schizophrenia but could also pose a massive challenge in how to address and help them.

May we live in interesting times…

Classification in Psychiatry presentation

Classification in Psychiatry - Presentation

Classification In Psychiatry

Categorisation 

http://www.youtube.com/watch?v=O8oAU3QGy2c 

Categorisation II

• Describe what you have just seen

• Probably used words like “goal” “football”   maybe even “Scotland”  or for the more advanced “good triumphing over evil”

• We experience raw streams of data that our brain subdivides into categories and concepts to help us make sense of this 

• We think abstractly using the same method of concepts/ categories

• This happens at basic animal levels of consciousness – “do we mate with it/ eat it/avoid or go round it/run away from it”?

Categorisation III

• Doctors often see patients in time critical situations e.g. brief appointments

• Other stressors could be e.g. seeing patient at 3am, being aware of multiple patients to see after this one, caseloads of 100s

• Often have to make decisions about patient such as admit/not admit, what treatment to start or change etc

• Need a robust system to help them make good decisions under alll kinds of pressure

A,B, C, D Model of Patient attributes

A - What patient shares with all other patients

B - What patient shares with some other patients

C – What is unique to this patient

{D- What patient shares with everybody else}

• If concentrate therapeutic efforts solely on A, offer same treatment to everyone

• If concentrate therapeutic efforts solely on C, can’t extrapolate from this patient how to treat other patients

• If concentrate purely on B lose sight of the person

• Must make therapeutic efforts on A,B,C and D

Why Do We Need Classification?

• Allows communication between professionals

• Allows groups to be defined for research to gain information on

• Range of likely outcomes (prognosis)

• Response to treatment

• Important correlates such as bio psycho social features

• Causes of the classified disorder (and explanation)

• Statistics for administration, management and budgeting

• Eligibility for care both from services but also family/society

• Facilitate appropriate payments for care

• Reduces potential for abuse e.g. of psychiatric diagnosis

The Status of a Diagnosis

• Diagnosis is an abstract concept used to summarise complex information about a patient’s health state

• It doesn’t exist as a “thing”

• It is ALWAYS provisional

• People may be given a diagnosis but they are NOT the diagnosis

• It can have powerful effects on people’s lives. Not all intentional or harmless

Essentialism & Carving Turkeys

• “Essentialism” suggests that for example illnesses can be separated into “natural kinds”

• These separate entities are distinguished by points of rarity and the categories have validity

• (Pneumonia is different from myocardial infarction, and can be further subdivided into a variety of aetiological causes)

• So diagnosis is supposed “to carve nature at the joints”

• BUT nature is not a giant multi-limbed turkey

• Mental disorder particularly hard to separate from each other

Promiscuous Reality and Elephants

http://www.youtube.com/watch?v=-Pknme2ahwA

What is Promiscuous Reality?

• Multiple viewpoints can describe a “piece” of the whole truth

• Putting all these viewpoints together can increase your knowledge of the whole though maybe not even the totality of whole truth

• Different viewpoints can have different purposes

• Multiple “models” of mental of disorder – biological, social, cognitive, psychodynamic and so forth

• These can all be useful in understanding and guiding help for patients

• They do not necessarily exclude each other

• Pragmatic realists recognise different classifications can be used depending on their Utility (usefulnesss)

Hepatic Lobule: multiple views

Can look at anatomical view : hexagonal structure

Can look at biliary flow point of view : centred on bile duct drainage area

All views valid and can choose which view suits your purpose.

What is Validity? I

• Construct validity. Construct validity refers to the extent to which a particular measure relates to other measures consistent with theoretically derived hypotheses

• Content validity refers to the extent to which a measure represents all facets of a given social construct (non-statistical expert opinion)

• Convergent validity refers to the degree to which a measure is correlated with other measures that it is theoretically predicted to correlate with e.g. intelligence test correlate with e.g. exam results

What is Validity? II

• Discriminant validity tests whether concepts or measurements that are supposed to be unrelated are, in fact, unrelated i.e. separates “natural kinds”

• Predictive validity measures how well the construct can predict future events ie. Prognosis  as well as treatment response

• Criterion validity. Criterion validity is measuring something that is external to the measuring instrument itself, called the criterion, that is representative of the construct. In medicine we often use biomarkers  e.g. BP, blood tests, X –rays etc

What is Validity? III

• Concurrent validity refers to the degree to which the construct description/ measures correlates with other measures of the same construct that are measured at the same time

• Face validity is a non-statistical  estimate of whether a test appears to measure a certain criterion; it does not guarantee that the test actually measures phenomena in that domain.

• Procedural validity. Procedural validity refers to the adequacy of a new diagnostic procedure in replacing or simulating some existing procedure e.g. use of standardised interviews to detect mental disorder over non-standardised. Not validity of construct itself.

Validity of Psychiatric Disorders (Robbins & Guze 1970)

1) Clinical Description (including symptom profiles, demographic characteristics, and typical precipitants),

2) Laboratory studies (including psychological tests, radiology and post mortem findings) extended to other external validators e.g. molecular biology, cognitive neuroscience

3) Delimitation from other disorders (by means of exclusion criteria)

4) Follow-up studies (including evidence of diagnostic stability), 

5) Family studies showing familial aggregation, specificity for same or related disorders

Validity of Psychiatric Disorders (Kendler 1980)

Antecedent validators 

• familial aggregation

• premorbid personality

• precipitating factors 

Concurrent validators 

• psychological tests (?external criterion?)

 Predictive validators 

• diagnostic consistency over time

• rates of relapse and recovery

• response to treatment

Lumpers v Splitters

• Lumpers emphasise lack of distinction between separate categories and high degree of comorbidity

• Splitters emphasise differences between members of bigger classes because of differences in treatment response / prognosis

Problems of classifying Mental Disorders

• Brain is most complex organ in body by far

• Functioning of brain poorly understood : what we do know is still difficult to understand how it translates into “outputs” such as thoughts, feelings, memories 

• (Physiology and pathophysiology poorly understood)

• “Outputs” of brain extraordinarily complex and affected by external factors such as culture and very hard to objectively measure

• Given complexity of outputs, the role of external factors such as culture, lack of knowledge of functioning of brain, difficulty objectively measuring outputs an aetiological classification is very difficult 

Reliability

• “Without Reliability there can be NO Validity (OR UTILITY)”

• If a diagnosis can’t be reliably agreed upon it has low utility

• Inter-Rater Reliability in terms of diagnosis can be defined as the degree to which different observers can agree on the presence of a diagnosis in the same patient

• Often measured using the Cohen’s kappa concordance statistic : the degree of agreement between 2 raters, greater than chance

• Also can be “weighted” for multiple categories, taking into account how close categories are together for agreement (e.g. yellow/orange more disagreement than red/violet)

Measuring Reliability

• Kappa Agreement

• < 0 Less than chance agreement

• 0.01–0.20 Slight agreement

• 0.21– 0.40 Fair agreement

• 0.41–0.60 Moderate agreement

• 0.61–0.80 Substantial agreement

• 0.81–0.99 Almost perfect agreement

(DSM 5 used much lower thresholds to justify diagnostic categories as having good reliability)

Inter-Rater reliability of ICD10 Diagnosis

For schizophrenia is substantial 0.79 – 81 but less so for subtypes 0.40- 0.74

For Personality disorder subtypes only slight to fair 0.07-0.43

Improving Inter-Rater Reliability of Diagnostic Agreement

• Standardising how and where patients are assessed

• Standardising what questions are asked

• Standardising training of raters

• Standardising how answers and observations are interpreted e.g. definitions of symptoms

• Standardising diagnostic definitions

• Standardising the rules how diagnosis are made e.g. in terms of co-morbid symptoms, co-morbid diagnosis, co-morbid aetiological factors e.g. substances

• NB Test-retest reliability 

Spectrum 

Many medical disorders exist on a spectrum which includes normality, the extremes of which clearly represent illness but with a "contentious" zone at more central values. An "expert committee" is usually formed which decides the best compromise for deciding a threshold. This threshold is often decided on the basis of associated poor outcomes such as death and other disease events.  Sometimes there is a threshold at only one end of the spectrum but often at both ends of a spectrum too

Examples include blood pressure, blood glucose, bronchial reactivity, depression/anxiety symptoms 

Within medical disorders often there can be mixed spectrum of clinical features and people can be put into separate diagnostic categories depending on which clinical features predominate . (Examples include mixes of bronchitis and emphysema, or psychosis and mania).

Utility of Colours

• Number of colours varies with culture e.g. Newton said 6, some cultures recognise only 2, others up to 7.

• Colours are cultural constructs separating spectrum into categories

• However people from all cultures are equally able to recognise difference in hues/shades 

• Recognising differences in colours has usefulness : in natural and artificial world. 

• PANTONE is a system of allocating codes to different shades so that manufacturers, printers, artists etc can communicate with each other and be consistent when using colours

Utility without Validity : SCZ and Mania

• Can reliably separate: ICD 10 kappa for schizophrenia 0.79-0.81 and for bipolar, manic disorders to be 0.69-0.77

• Has predictive value for outcome: AESOP study if presented with Mania had 3-4 times better chance of symptom & functional recovery at 3 and 10 years than presenting with Schizophrenia

• Has predictive value for treatment: Lithium effective in bipolar mania (and bipolar, depression) but not schizophrenia. Antipsychotics can be effective for  both bipolar mania and schizophrenia but not bipolar, depression (quetiapine low dose may be effective for bipolar dep)

• Bipolar on average less cognitive impairment than SCZ

• More likely to have same type of disorder inherited (not purely tho)

Diagnosis 0.0

• These are problems that may be the focus of clinical attention or may be referred to clinicians for help

• Not usually “illnesses” per se with a “disease” cause but often mixed groups and very culturally based

• Often need a diagnostic “code” to enable someone to access help and for the clinician to be remunerated (or allowed to help)

• Maybe contentious as some do not feel should be “medical”

• Examples include relationship problems, Oppositional Defiance Disorder,  anger management issues, ?paraphillias, some plastic surgery problems

Diagnosis 1.0

• Descriptions of clinical states that are problematic and widely thought to need medical attention

• Often describe  syndromes i.e. collections of clinical features occur together , often little validity to the distinctions

• Not aetiological i.e. not based on cause of the disorder so members of this group often have different causes (known or unknown)

• As not aetiological not able to “explain” and treatment responses /outcomes highly variable, lack of lab tests; cultural limitations

• Many psychiatric disorders e.g. depression, schizophrenia, ADHD, also “functional” medical disorders and e.g. “fever”

Diagnosis 2.0

• Fully aetiological basis known and external validating criteria such as lab tests to confirm diagnosis and monitor progress

• More able to sort in to truly valid categories

• As aetiological basis known, better able to predict outcomes and treatment responses, develop new treatments

• Explanation of disorder known : greater patient information and public health interventions possible

• Many medical conditions but also e.g. alzheimer’s disease, wernicke-korsakoff, steroid induced depression

Stigma and other drawbacks 

• By concentrating on the diagnosis can lose whole picture especially if “overforce” into ill matching category

• Stigma: people often get associated with their diagnosis e.g. epileptic, diabetic

• This can lead to self-stigma, stigma from other people, and from healthcare professionals based on stereotypes of that illness

• This stigma can be even more distressing than the disorder itself

• Reification “over estimate” the degree of “predictive knowledge” and “validity” of the diagnostic construct e.g. SCZ is an illness not a disease (as pathology unknown in most cases)

Comparison with General Medical Diagnosis  Szasz fallacy

• Disease can only mean something people "have," while behavior is what people "do". Diseases are "malfunctions of the human body, of the heart, the liver, the kidney, the brain" while "no behavior or misbehavior is a disease or can be a disease. That's not what diseases are.”

• Says mental illnesses are metaphors

• Ignores the conceptual basis of general medicine

• Assumes all general medical problems have identified pathology

• Ignores value judgements made even in “objective” lab tests

• Assumes perfect knowledge of pathology and physiology

Diagnosis in Medicine – Problems

• 60% of MDDUS negligence claims v GPs  are due to failure to diagnose

• Diagnostic errors are the most common source of the medical malpractice payments, the most costly and the most dangerous when it came to patients’ health

• A systematic review of studies of the autopsy calculated that in about 25% of autopsies a major diagnostic error will be revealed. 

• This rate has decreased over time and the study projects that in a contemporary US institution, 8.4% to 24.4% of autopsies will detect major diagnostic errors.

Causes of Diagnostic Errors 1

• Anchoring bias (COMMONEST) – locking on to a diagnosis too soon and failing to adjust to new information.

• Availability bias – thinking that a similar recent presentation you have encountered is also happening in the present situation.

• Confirmation bias – looking for evidence to support a pre-conceived opinion or notion, rather than looking for information to prove oneself wrong.

• Diagnosis momentum – accepting a previous diagnosis without applying sufficient scepticism.

Causes of Diagnostic Errors 2

• Overconfidence bias – Over-reliance on one’s own ability, intuition and judgement.

• Premature closure – similar to confirmation bias, but more like jumping to a conclusion.

• Search-satisfying bias – A “eureka” moment that stops all further thought on the matter

I would also add 

• treating the test result not the patient

• “over-forcing” patient into a diagnostic category they don’t fit well into

Comparison with Medical Diagnosis Reliability

• “…most indexes of agreement between pathologists ranged from poor (needle biopsy 0.21) to moderate (necropsy/surgery 0.57).” 

• 160 cases reviewed  3 pairs of neurologists “with a special interest in stroke.”8 The kappa was only “fair to good” in most categories of ischemic stroke, with a high of 0.70 for oral contraceptive-related stroke and a low of 0.28 for lacunar infarcts; the average kappa for all categories was 0.53 

• Knee osteoarthritis kappa = 0.1 renal artery stenosis kappa =0.43

• that interrater reliability is no higher in many nonpsychiatric medical specialties than in psychiatry 

Comparison with Medical Diagnosis Validity

• Many medical problems have unknown pathology and would fail to meet “validity” tests

• Headaches, migraines, CFS/ME, Fibromyalgia Irritable Bowel Syndrome

• Up to 40% of referrals to different medical OPs have these “functional disorders”

• May medical problems have “cultural” overlays in presentation e.g. myocardial infarction

• Even when pathology known and "validity gap", often general medical treatments have similar effectiveness to psychiatric treatments

Comparison with Medical Diagnosis  Spectrum

• Many accepted medical disorders lie on a spectrum with “normality”

• Examples include hypertension, non insulin dependent diabetes, asthma

• Many medical disorders don’t have clear cut boundaries with similar disorders

• Example: bronchitis/emphysema, unstable angina/myocardial infarction

History of Classification – Early Days

• Initially mental disorders thought to be somatic in origin

• Gradually introduction of ideas of “mental” disorders with varying degree of somatic input 

• Every country, every hospital sometimes even every psychiatrist had a separate diagnostic system

• Research papers often had to include lengthy descriptions of each patient so that readers could compare to own patients e.g. Aubrey Lewis paper on depression 40-50 pages had 20 pages on describing each patient

• Psychodynamic classifications important in US from early-mid 20th C

US/UK Diagnostic Project

• Noted high rates of schizophrenia in US especially New York compared to UK

• Group of London psychiatrists visited NY in late 65-70 and using standardised psychiatric interviews and a standardised way of making psychiatric diagnosis

• Found high rates of schizophrenia in New York due to their use of a “psychodynamic” diagnostic criteria, many of these cases would be diagnosed with mood disorders or personality disorders in the UK

• Highlighted the variability of diagnostic practices reduced its’ usefulness for research or communication or statistics or clinical practice

Nomenclature & Classification

• Nomenclature refers to the naming of objects in  a classification

• These objects are given a description , often with a definition of what is unique to that object

• The combination of nomenclature of objects with their descriptions is called a glossary 

• The classification ideally should be mutually exclusive and jointly exhaustive : every example (e.g. of clinical cases) described and examples can only be put in 1 place

• A Taxon is a group of objects with obvious and important similarities 

• Taxonomic hierarchy often used e.g. classification of animals

ISPS (1967) and DOSMED (1992)

• Multiple international centres of research in broad spread of developed and developing countries

• Used standardised semi-structured interviews and diagnostic procedures

• “Broad” definition of psychosis  incidence varied widely by country 

• “Narrow” definition of psychosis roughly similar incidence across globe- adding to cross-cultural validity of concept of “Schneiderian” SCZ

• Outcomes generally better in developed countries ?less EE ?different aetiology?

Diagnostic Hierarchy

Choose diagnosis that is highest in hierarchy that can explain all symptoms 

1. Organic disorders
2. Mood Psychosis
3. Schizophrenia
4. Depression
5. Anxiety Disorders
6. Personality issues

Prototypic Matching/ Narrative v Operational Criteria

• Prototypic matching/  narrative classifications describe “typical cases” (cf blue bloaters/pink puffers). Professionals match patient in front of them to closest description in classification 

• Clinicians prefer this type as quick and convenient

• Operational criteria list a set of rules to make a diagnosis in a particular patient (cf making a diagnosis of myocardial infarction) such as mandatory features, exclusion criteria etc. 

• Researchers prefer this as more get more standardised homogenous groups

Multi-axial Classification

• With most diagnosis often non-aetiological, often ignoring social circumstances, high rates of comorbidity

• Can list important factors in different “axes”

• Eg. DSM III & IV had

1. • Clinical syndromes/disorders
2. • Personality disorders, mental retardation
3. • Medical conditions
4. • Psychosocial and Environmental Stressors
5. • Global Assessment of Functioning

The International Classification of Diseases

• The standard diagnostic tool for epidemiology, health management and clinical purposes.

• Every country has to send health statistics using ICD codes to UN

• In its 10th edition, with 11th coming out soon

• 6th edition started providing psychiatric codes but with no description (similar to other health problems) 

• From 8th edition onwards a “glossary” produced with descriptions of each psychiatric code to improve standardisation of practice

• 10th has a main version of a  glossary with prototypic descriptions, a DCR with operational criteria and a simplified primary care version

Diagnostic Statistical Manual

• Introduced to produce codes for variety of admin uses and descriptions of these codes for US 

• Gives ICD codes for disorders and increasing similarity to ICD

• DSM editions I,II used psychodynamic concepts and aetiology

• DSM III revolutionary in 1980 : operational criteria, multi-axial classification, dropped Freudian aetiology, aimed for reliability

• Latest edition DSM V controversial: felt to be too low thresholds to include too many “contentious” cases (Yanks worry though that too restrictive would deny people access to help)

• Most commonly used system in research

Alternative Diagnostic Systems

• France uses a psychodynamic influenced classification for child psychiatry

• ICD as has to be used internationally incorporates many of different traditions of psychiatric diagnostic practices in their classification

Diagnosis as part of Formulation

• Formulation is summary of all relevant clinical information including diagnosis

• Should guide treatment and management of patient

• Should tell you “why does this patient present with this type of problem at this particular time (and still does)?”

• Can be divided into predisposing, precipitating and maintaining factors

• The types of factors can be divided into biological, psychological and social

• BIOPSYCHOSOCIAL formulation

Alternatives to Diagnosis: Why?

• Lack of validity

• High rates of comorbidity

• High levels of assumptions contained within diagnosis

• Dislike of “medical” emphasis/language/system and perceived “biological orientation” “Disease based model”

• Diagnostic system may not suit their practice: 

• e.g. primary care where the cause of the stress (usually psychosocial) & most often mixed anxiety and depressive symptoms

• Psychotherapists and psychologists with “office based practice”

• Ignores social context & locates pathology in individual

Alternatives to Diagnosis : Symptoms

• Can just use symptoms : no assumptions about relationships or associations so no concerns re : validity

• Individual symptoms can have some predictive validity

• “most scientific” as just concentrate on what is present and can measure these

• Some treatments such as eg CBT focus on individual symptoms

• Very time and cognitive resource intensive

• Often “diagnosis by proxy” as have to take into account aetiology eg substance-related anxiety treated differently than free floating

• Often medical treatments effect multiple symptoms at same time

Alternatives to Diagnosis : Dimensions

• Dimensions are  Groups symptoms/clinical features  into categories of related symptoms 

• Often describes patients better than simple diagnosis (1 bit v multiple bits) in terms of clinical picture, prognosis and treatment responses

• Also requires additional aetiological information 

• Often prone to diagnosis e.g. describing patients with high levels of hallucinations/delusions as “paranoid schizophrenia” in head

• Complexity can be hard to hold and manipulate in head whilst making decisions as well as collecting statistics, research (due to large no. of groups so often use correlation)

• Multiple dimensions become like diagnostic comorbidity 

Alternatives to Diagnosis : Purely Psychosocial formulations

• DCP trying to develop “paradigm shift” 

• Intent is to provide a narrative formulation with less emphasis on biological factors

• Trying to identify psychological processes as basis of classification

• More useful therefore for psychotherapy and “office based practice”

• Unknown reliability and validity

• Unlikely to be useful to “medical psychiatry”

• Issues of communication errors if used exclusively by psychologists when talking to psychiatrists

Further Reading

• ICD 10 (mandatory until ICD 11 comes out)

• DSM V (know about)

• “A Companion to the Classification of Mental Disorders” Cooper and Sartorius

• Read chapter on Classification in your main textbook e.g. Shorter Oxford Textbook on Psychiatry 

• “Distinguishing between the validity and utility of psychiatric diagnoses” Kendell, Robert;Jablensky, Assen The American Journal of Psychiatry; Jan 2003; 160, 1

• “Models for Mental Disorder”  Tyrer and Steinberg

• Philosophical Issues in Psychiatry Volume 2: Nosology