Some critics argue that the types of psychiatric diagnosis found in the Diagnostic and Statistical Manual of Mental Disorders and International Classification of Disease are superfluous and should be abandoned. These are known as categorical polythetic psychiatric diagnoses. To receive a categorical polythetic psychiatric diagnosis an individual need only exhibit some, rather than all, of the symptoms on the diagnostic criteria. Consequently, categorical polythetic psychiatric diagnoses only associate an individual with a range of symptoms rather than specify which symptoms they (...) have. Drawing on Giere’s account of scientific models, I portray categorical polythetic psychiatric diagnoses as abstract models that guide the building of less abstract models. These models can specify which symptoms a particular individual has. Additionally, categorical polythetic psychiatric diagnoses can guide investigation of symptoms towards difficult to spot symptoms, guide investigation towards changing symptoms, and guide investigation towards how symptoms manifest. These important roles mean categorical polythetic psychiatric diagnoses should not be abandoned. (shrink)

Psychiatric researchers typically assume that the modelling of psychiatric symptoms is not influenced by psychiatric categories; symptoms are modelled and then grouped into a psychiatric category. I highlight this primarily through analysing research domain criteria. RDoC’s importance makes it worth scrutinizing, and this assessment also serves as a case study with relevance for other areas of psychiatry. RDoC takes inadequacies of existing psychiatric categories as holding back causal investigation. Consequently, RDoC aims to circumnavigate existing psychiatric categories by directly investigating the (...) causal basis of symptoms. The unique methodological approach of RDoC exploits the supposed lack of influence of psychiatric categories on symptom modelling, taking psychiatric symptoms as the same regardless of which psychiatric category is employed or if no psychiatric category is employed. But this supposition is not always true. I will show how psychiatric categories can influence symptom modelling, whereby identical behaviours can be considered as different symptoms based on an individual’s psychiatric diagnosis. If the modelling of symptoms is influenced by psychiatric categories, then psychiatric categories will still play a role, a situation which RDoC researchers explicitly aim to avoid. I discuss four ways RDoC could address this issue. This issue also has important implications for factor analysis, cluster analysis, modifying psychiatric categories, and symptom based approaches. (shrink)

Volume 20, Issue 4, May 2020, Page 44-45.

Critics who are concerned over the epistemological status of psychiatric diagnoses often describe them as being constructed. In contrast, those critics usually see symptoms as relatively epistemologically unproblematic. In this paper I show that symptoms are also constructed. To do this I draw upon the demarcation between data and phenomena. I relate this distinction to psychiatry by portraying behaviour of individuals as data and symptoms as phenomena. I then draw upon philosophers who consider phenomena to be constructed to argue that (...) symptoms are also constructed. Rather than being ready made in the world I show how symptoms are constructs we apply to the world. I highlight this with a historical example and describe methodological constraints on symptom construction. I show the epistemic problems with psychiatric diagnoses are also applicable to symptoms. Following this, I suggest that critics of psychiatric diagnoses should extend their criticism to symptoms or, if they still believe symptoms are relatively epistemologically unproblematic, should rethink their concerns over psychiatric diagnoses. (shrink)

Historians and sociologists of psychiatry often claim that psychiatric diagnoses are discontinuous. That is, a particular diagnoses will be described in one way in one era and described quite differently in a different era. Historians and sociologists often draw epistemic consequences from such discontinuities, claiming that truth is pluralistic, provisional and historicised. These arguments do not readily fit in with how analytical philosophers of science approach scientific realism. I show how the pessimistic meta induction does not capture the point which (...) historians and sociologists are making but scientific perspectivism seems to capture their point much better. I then highlight conceptual innovations which scientific perspectivists add. They demarcate between truth and objective reality, they specify which type of truth they endorse and they put down constraints on possible truths. This blocks an anything goes relativism which historians and sociologists can be in danger of falling into. I highlight my argument by discussing a discontinuous episode in the history of autism. I discuss three aspects of this discontinuity and show how scientific perspectivism can portray each aspect as non-trivially true. My argument shows that we can be scientific realists about autism even if we can formulate notions of autism in quite different ways. (shrink)

Self-diagnosis in psychiatry is where individuals diagnose themselves rather than rely upon official diagnosticians to supply a psychiatric diagnosis. The accuracy of self-diagnosis is a contested topic. In this paper, I outline what arguments are needed to see self-diagnosis as accurate and how different approaches to self-diagnosis require different arguments. I show how different arguments are required to justify accuracy for an autistic individual judging they are autistic compared to non-autistic individuals judging they are not autistic. Different arguments are required (...) if a self-diagnosing individual accepts or rejects official diagnostic criteria. Finally, different arguments are required depending upon whether diagnoses are seen as objective entities, the product of theoretical virtues or practically useful groupings. All these approaches require unique arguments to justify the accuracy of self-diagnosis. Identifying the required arguments for different approaches is a stepping stone toward establishing whether those arguments and which of those arguments can be successfully justified. (shrink)

I suggest that the diagnosis that an individual self-diagnoses with can be influenced by levels of public awareness. Accurate diagnosis requires consideration of multiple diagnoses. Sometimes, different diagnoses can overlap with one another and can only be differentiated in subtle and nuanced ways, but particular diagnoses vary considerably in levels of public awareness. As such, an individual may meet the diagnostic criteria for one diagnosis but self-diagnoses with a different diagnosis because it is better known. I then outline a potential (...) negative consequence of this. Psychiatric diagnoses can grant access to what I call social resources, namely, political advocacy, campaigning for support, participating in scientific research, building diagnostic cultures, and opportunity for social interactions with people who have the same diagnosis. The strength of the social resources for a particular diagnosis can be made stronger when more people have that diagnosis. As such, inaccurate self-diagnosis can result in the social resources for one diagnosis being strengthened whilst not being strengthened in relation to another diagnosis in comparison to accurate diagnosis. This shows how inaccurate self-diagnosis can alter the distribution of social resources. We need to consider whether this is unfair to people who are diagnosed with less well-known conditions. (shrink)

Philosophers of science have recently called for experts-by-experience to be involved in revising psychiatric diagnoses. They argue that experts-by-experience can have relevant knowledge which is important for considering potential modifications to psychiatric diagnoses. I show how altering one diagnosis can impact individuals with a different diagnosis. For example, altering autism can impact individuals diagnosed with Attention Deficit Hyperactivity Disorder and Schizoid Personality Disorder through co-morbidity and differential diagnostic criteria. Altering autism can impact the population making up the diagnosis of Attention (...) Deficit Hyperactivity Disorder and Schizoid Personality Disorder which can then influence which behaviour each diagnosis covers and which parts of the causal structure each diagnosis covers. Expanding one diagnosis can mean, if differential diagnostic criteria are present, that individuals who have a different diagnosis, or would one day have been diagnosed with that different diagnosis, are instead now diagnosed with the expanded diagnosis. Alternatively, if two diagnoses can be co-morbid then expanding one diagnosis can mean individuals who have a different diagnosis can now also receive the expanded diagnosis. Changing these can then impact the adequacy of symptoms formulated to cover behaviour and causal mechanisms formulated to cover the causal structure. This means experts-by-experience representing a range of diagnoses should be involved in decisions over modifying diagnoses they do not have. For example, Attention Deficit Hyperactivity Disorder individuals should be involved in decisions to modify autism. I discuss practical issues relating to how much say people with a range of diagnoses should have in relation to modifying a diagnosis which they do not have. We should employ a principle of equality whereby the level of say individuals with one diagnosis should have on another diagnosis should be equally reciprocated. (shrink)