The psychiatric interview for differential diagnosis

The Psychiatric
Interview for
Differential Diagnosis

Lennart Jansson
Julie Nordgaard

123


The Psychiatric Interview for Differential
Diagnosis



Lennart Jansson • Julie Nordgaard

The Psychiatric Interview
for Differential Diagnosis


Lennart Jansson
Mental Health Center Hvidovre
University Hospital of Copenhagen
Broenby
Denmark

Julie Nordgaard
Early Psychosis Intervention Center
Region Zealand & Institute
for Clinical Medicine

University of Copenhagen
Broenby
Denmark

ISBN 978-3-319-33247-5
ISBN 978-3-319-33249-9
DOI 10.1007/978-3-319-33249-9

(eBook)

Library of Congress Control Number: 2016944150
© Springer International Publishing Switzerland 2016
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Foreword

This book fills a substantial gap in contemporary psychiatry and is written by two
researchers and clinicians who have in-depth knowledge and scholarship in psychopathology. Psychiatry is currently in a state of profound crisis, from time to time
acknowledged in major journals (Andreasen 2007; Kleinman 2012).
This crisis contains several independent components, first the diagnostic manuals have bred ever new categories and this proliferation has resulted in approximately 400 categories in the DSM and ICD systems. We have no etiological
knowledge of the vast majority of these categories and we do not know much about
their treatment. It is even doubtful if they all should be the matter of psychiatry
(Ghaemi 2012). As it has been demonstrated by a Danish epidemiological study
(Munk-Jorgensen et al. 2010), clinicians would be happy with approximately 20
categories. Choosing the most relevant diagnosis (differential diagnosis) between
400 categories is, of course, a matter for a computer and not for a human being.
The second component of the crisis is an increasing gap between a brilliant progress in basic neuroscience and its complete lack of consequences for clinical psychiatry (Hyman 2010). Clinical psychiatry is in a state of stagnation and new
inventions and the treatment innovations come from people working on the ground
and not from psychiatric academia.
The third component of importance and perhaps the root problem of psychiatry
is the nature of the diagnostic system itself. In the preparations for DSM-III, the
idea was to define its diagnostic categories by a prototypical narrative description
supplemented by a list of selected symptoms that clinicians were obliged to complete. In the final production of DSM-III, the prototypes were abandoned and diagnoses defined by a sufficient number of symptoms from specific lists. It was naively
believed that symptoms could be defined in a so-called operational way (Parnas and
Bovet 2015). In these systems, the symptoms are considered as well-demarcated,
mutually independent, thing-like objects, which can be unproblematically registered and quantified. The specific lists of symptoms for each diagnostic category
were limited to a number of symptoms believed to be characteristic, as “gate keepers” to diagnosis. This entailed the disastrous consequence that the listed criteria
came to be considered as the exhaustive description of the category in question, in
other words, vast domains of psychiatry has gone into oblivion because psychiatric
textbooks typically limit their psychopathological section to reprinting the DSM
criteria.
v


vi

Foreword

The symptoms, which are shared by different disorders, were eliminated from
the diagnostic systems in order to sharpen the boundaries of the categories. Thus,
for example, it is often a novelty for a psychiatrist to hear that anxiety is a common
feature of beginning schizophrenia.
These epistemological deformations of the object of psychiatry (symptoms and
signs) have undoubtedly contributed to a lack of research progress and to a situation
where the diagnostic process is basically reduced to an “associative event”: when a
patient presents with a complaint of being down, it is likely that he will be diagnosed with depression, and, if he says that he cuts himself, it is likely that he will
receive the diagnosis of borderline. We also observe epidemics of certain mental
disorders such as ADHD, autistic spectrum, etc., epidemics reflective of the problems of differential diagnosis in the operational systems (Parnas 2015).
A separate but closely related problem is that of interviewing the patient. We
have empirically demonstrated that a fully structured interview is an absurdity
(Nordgaard et al. 2012), and we have provided a detailed theoretical explanation in
a separate paper (Nordgaard et al. 2013). The problem put very simple is that psychiatrists are not trained in conducting a psychiatric interview in a way that is phenomenologically correct, i.e., that allows the symptoms to emerge and articulate
themselves in a quasi-natural conversation between the patient and the doctor. This
volume describes certain basics of the psychiatric interview that have to be adopted
in order to conduct an interview, which is maximally informative.
The symptom is not an isolated piece but typically depends on the context and
larger wholes to which it belongs (Nordgaard et al. 2013). This book attempts to
restore the basic knowledge of psychopathology and of the epistemic process
involved in making psychiatric diagnoses. It provides a useful catalog of psychopathological descriptions based on a massive body of classic and modern psychopathological literature. It also restores a prototypical approach to diagnosis,
explained very simple: when we see a patient we see him as a certain person in a
specific context; if it is a 40-year-old male, still living with his mother, only leaving
the apartment at night, and complains of “feeling down” it is unlikely that the cardinal problem is an affective disorder. These processes of typification and their relevance for diagnoses are explicated in detail in this book.
This volume is primarily addressing clinical psychiatrists and psychologists,
psychiatric residents, and people involved in psychiatric research. It is also helpful
to psychiatric nursing staff and other paramedical personnel involved in the treatment of psychiatric patients.

Copenhagen, Denmark
2016

Josef Parnas


Foreword

vii

References
Andreasen NC (2007) DSM and the death of phenomenology in america: an example of unintended consequences. Schizophr Bull 33(1):108–112. doi:sbl054 [pii] 10.1093/schbul/sbl054
Ghaemi SN (2012) Taking disease seriously: beyond pragmatic nosology. In: Kendler K, Parnas J
(eds) Philosophical issues in psychiatry II. Nosology. Oxford University Press, Oxford,
pp 42–53
Hyman SE (2010) The diagnosis of mental disorders: the problem of reification. Annu Rev Clin
Psychol 6:155–179
Kleinman A (2012) Rebalancing academic psychiatry: why it needs to happen – and soon. Br J
Psychiatry 201(6):421–422. doi:10.1192/bjp.bp.112.118695
Munk-Jorgensen P, Najarraq Lund M, Bertelsen A (2010) Use of ICD-10 diagnoses in Danish
psychiatric hospital-based services in 2001–2007. World psychiatry 9(3):183–184
Nordgaard J, Revsbech R, Saebye D, Parnas J (2012) Assessing the diagnostic validity of a structured psychiatric interview in a first-admission hospital sample. World psychiatry
11(3):181–185
Nordgaard J, Sass LA, Parnas J (2013) The psychiatric interview: validity, structure, and subjectivity. Eur Arch Psychiatry Clin Neurosci 263(4):353–364. doi:10.1007/s00406-012-0366-z
Parnas J (2015) Differential diagnosis and current polythetic classification. World psychiatry
14(3):284–287. doi:10.1002/wps.20239
Parnas J, Bovet P (2015) Psychiatry made easy: operation(al)ism and some of its consequences. In:
Kendler K, Parnas J (eds) Philosophical issues in psychiatry III: the nature and sources of historical changes. Oxford University Press, Oxford, pp 190–212

Contents

1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Part I The Diagnostic Interview
2

Validity and Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 The Concept of Validity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1.1 Validity of Allocating Psychiatric Diagnoses . . . . . . . . . . . .
2.2 The Concept of Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.1 Reliability of the Diagnostic Systems . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9
9
11
13
14
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3

The Psychiatric Interview: Theoretical Aspects . . . . . . . . . . . . . . . . . . .
3.1 Typification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 The Gestalt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.3 Cartesian Dualism: The Inner and Outer . . . . . . . . . . . . . . . . . . . . . .
3.4 Experiences and Expressions: Consciousness . . . . . . . . . . . . . . . . . .
3.5 The Phenomenological Approach . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17
18
19
20
21
23
24

4

The Psychiatric Interview: Methodological and Practical
Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 The Fully Structured Interview . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 The Unstructured Interview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 The Semi-structured Interview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 Structured Versus Semi-structured Interview . . . . . . . . . . . . . . . . . .
4.5 Rapport and the Interviewer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6 How to Conduct the Psychodiagnostic Interview . . . . . . . . . . . . . . .
4.7 Different Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.8 Difficult Interviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.8.1 The Suspicious, Guarded Patient . . . . . . . . . . . . . . . . . . . . . .
4.8.2 The Withdrawn, Psychotic Patient . . . . . . . . . . . . . . . . . . . . .
4.8.3 The Threatening, Aggressive Patient . . . . . . . . . . . . . . . . . . .
4.8.4 The Severely Exalted Patient . . . . . . . . . . . . . . . . . . . . . . . . .
4.8.5 The Suicidal Patient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

27
29
33
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36
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49
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5

Mental State Examination: Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1 Appearance and Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2 Motor Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.1 Catatonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5.2.2 Compulsions/Pseudocompulsions . . . . . . . . . . . . . . . . . . . . .
5.2.3 Extrapyramidal Side Effects of Antipsychotic
Medication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Eye Contact and Gaze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4 Rapport. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5 Mood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6 Affects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.7 Speech and Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.7.1 Formal Thought Disorders . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.8 Cognition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9 Self-Harm and Suicidal Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Part II The Diagnostic Spectra

6

7

Navigating Between the Spectra: Organic Disorders,
Schizophrenia, Affective Disorders, Personality Disorders,
and Situational Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1 The Process of Differential Diagnosis . . . . . . . . . . . . . . . . . . . . . . . .
6.1.1 The Prototypical Approach . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.2 The Operational Approach. . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2 Diagnostic Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3 The Specificity of Psychopathology . . . . . . . . . . . . . . . . . . . . . . . . .
6.4 Existential Patterns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.5 Diagnostic Overlaps and Comorbidity. . . . . . . . . . . . . . . . . . . . . . .
6.6 The Borders of Normality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7 Diagnostic Slippage and Neglect . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Considering Organic Pathology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1 General Aspects of Organic Psychopathology. . . . . . . . . . . . . . . . .
7.2 The Psychiatric Expressivity of Organic Brain Disease . . . . . . . . .
7.3 Organic States Hard to Recognize . . . . . . . . . . . . . . . . . . . . . . . . . .
7.4 Organic States Mimicking Functional Mental Illness . . . . . . . . . . .
7.4.1 Organic (Secondary) Psychosis . . . . . . . . . . . . . . . . . . . . . .
7.4.2 Organic Paranoid and Schizophrenia-Like Psychosis . . . . .
7.4.3 Organic Mood Disorders . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.4.4 Organic Anxiety and Obsessive-Compulsive
Phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.4.5 Organic Personality Change . . . . . . . . . . . . . . . . . . . . . . . .
7.5 Mental Illness Mimicking Organic States . . . . . . . . . . . . . . . . . . . .
7.5.1 Pseudodementia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7.5.2 Pseudodelirium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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7.5.3 Functional Neurological Disorders . . . . . . . . . . . . . . . . . . . 122
7.5.4 Factitious Disorder and Malingering . . . . . . . . . . . . . . . . . . 123
Literature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
8

Indicators of Psychosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.1 Psychosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2 The Diagnostic Criteria of Schizophrenia . . . . . . . . . . . . . . . . . . . .
8.3 The Clinical Core Gestalt of Schizophrenia . . . . . . . . . . . . . . . . . .
8.4 Near-Psychotic Phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5 Transition to Psychosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.6 The Course and Clinical Variation of the Schizophrenia
Spectrum Disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.7 The Problems of Early Detection of Schizophrenia . . . . . . . . . . . .
8.8 Other Non-affective Psychoses . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.9 The Differential Diagnosis of the Autism Spectrum . . . . . . . . . . . .
8.10 Psychotic Phenomena in the General Population . . . . . . . . . . . . . .
8.11 Disclaiming Psychopathology in Psychosis. . . . . . . . . . . . . . . . . . .
8.12 The Expressivity of the Schizophrenia Spectrum . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

129
130
131
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141
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9

Varieties of Depressive-Like Mental States . . . . . . . . . . . . . . . . . . . . .
9.1 The Diagnostic Criteria of Depression . . . . . . . . . . . . . . . . . . . . . .
9.2 The Different Meanings of Depression . . . . . . . . . . . . . . . . . . . . . .
9.2.1 Nuclear Depression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2 Paradepression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3 Pseudo-depression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.4 Depression in Schizophrenia . . . . . . . . . . . . . . . . . . . . . . . .
9.2.5 Subclinical, Atypical, and Transcultural Depression . . . . . .
9.2.6 Psychotic Depression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3 The Course of Depression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.4 The Expressivity of Depression . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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10

Varieties of Anxiety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.1 Anxiety as Mood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2 Panic Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.3 Social Anxiety (Social Phobia) . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.4 Obsessive-Compulsive Phenomena . . . . . . . . . . . . . . . . . . . . . . . .
10.5 Hypochondriasis and Dysmorphophobia . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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11

Bipolar Disorder and Acute Psychosis . . . . . . . . . . . . . . . . . . . . . . . . .
11.1 Bipolar Disorder: Mania, Hypomania, and Mixed States . . . . . . .
11.1.1 Mania . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.1.2 Hypomania . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.1.3 Mixed States. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.1.4 The Differential Diagnosis of Mania . . . . . . . . . . . . . . . . .

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11.1.5 The Bipolar Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.1.6 The Course of Bipolar Disorder. . . . . . . . . . . . . . . . . . . . .
11.2 Acute Non-organic Psychoses . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.3 Acute Schizophrenia and Schizoaffective Disorder . . . . . . . . . . . .
11.4 Substance-Related Psychoses . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Detecting Disordered Personality Pattern . . . . . . . . . . . . . . . . . . . . . .
12.1 Personality Disorder. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.2 The Recognition of Specific Personality Disorders . . . . . . . . . . . .
12.3 Patterns of Personality Disorder . . . . . . . . . . . . . . . . . . . . . . . . . .
12.3.1 The Obsessive-Compulsive Style . . . . . . . . . . . . . . . . . . .
12.3.2 The Paranoid Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.3.3 The Hysterical Style. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.4 Impulsive Personalities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.5 The Differential Diagnosis Between Personality Disorder
and Other Mental Illnesses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.6 Temperament as Premorbid Traits of Mental Illness . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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13

Thinking Adult in Adolescent Psychiatry . . . . . . . . . . . . . . . . . . . . . . .
13.1 The Early Course of Schizophrenia . . . . . . . . . . . . . . . . . . . . . . . .
13.2 Schizophrenia Versus Autism Spectrum Disorders . . . . . . . . . . . .
13.3 The Early Course of Affective Disorders. . . . . . . . . . . . . . . . . . . .
13.4 Anxiety Disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13.5 Personality Disorder and Adolescence . . . . . . . . . . . . . . . . . . . . .

13.6 Attention Deficit Hyperactivity Disorder. . . . . . . . . . . . . . . . . . . .
13.7 The Effects of Substance Use/Abuse . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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252
252
253
253
254

14

Concluding Chapter: The Diagnostic Process . . . . . . . . . . . . . . . . . . . 257

12

243
244
245

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261


1

Introduction

What matters most are not the symptoms
but the mental state that conditions them
Minkowski quoting Binet and Simon

Making the correct diagnosis is a prerequisite for deciding the right treatment strategy. Without paraclinical aids, psychiatry is left to make its diagnoses by the diagnostic interview. The diagnostic manuals contain an increasing number of categories
to choose among, which share a huge number of apparently nonspecific features,
complicating the diagnostic process. These categories no longer purport to be nosological entities but merely syndromal “disorders” describing certain prominent features, a fact that explains why DSM encourages ample comorbidity diagnoses. In
spite of the introduction of standardized and operationalized systems, misdiagnosis
is rampant in clinical psychiatry and even in research.
The discipline of differentiating between similar diagnostic presentations is
named differential diagnosis. There is no universally agreed upon definition of this.
Merriam-Webster () has “The distinguishing of a
disease or condition from others presenting with similar signs and symptoms,” and
Encyclopædia Britannica () states that “The clinician
uses the information gathered from the medical history and physical and mental
examinations to develop a list of possible causes of the disorder, called the differential diagnosis.” So, differential diagnosis has to do with choosing between a number
of listed alternative conditions in the light of information gathered from different
sources, the pivotal procedure in psychiatry being the diagnostic interview. This
book deals with the psychiatric interview for the differential diagnosis.
Different approaches to differential diagnosis have been put forward over the
years. In the days of prototypical diagnoses, differential diagnosis was informed by
clinical observation of differences between diverse mental states (e.g., Weitbrecht
1966), and after the so-called operational revolution culminating with the DSM-III
in 1980, it became a matter of diagnostic algorithm, e.g., in First (2014) who presents a step-by-step procedure starting from the chief complaints, ruling out medical
conditions, etc., and following “decision trees” to find the condition, which can best
account for the symptoms. An algorithm thus based on diagnostic criteria (of

© Springer International Publishing Switzerland 2016
L. Jansson, J. Nordgaard, The Psychiatric Interview for Differential Diagnosis,

DOI 10.1007/978-3-319-33249-9_1

1


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Introduction

DSM-5, in this case) sets a limit to the refinement of the diagnosis. Confined to
these criteria, it will inevitably ignore the psychopathological Gestalt informed by
psychopathology and psychopathological context not incorporated in these
criteria.
Very few psychopathological phenomena are specific for any condition; most are
seen in a variety of disorders, e.g., anxiety, attentional deficits, and cutting, all
reflecting that “something is not right.” To determine the more basic disturbance of
the phenomena requires some interviewing efforts to extract the salient profile of the
presented distress. It is unlikely that a checklist, of say depressive or ADHD features, has an adequate potential to clarify the matter. There is no other way than
talking with the patient and illuminating his experience in its context of other experiences, expressions, behaviors, and developmental historical aspects (Parnas 2012).
In our view, this book fills a gap in the psychiatric literature on the clinical interview for differential diagnosis. With this book, we wish to outline the basic principles of the diagnostic process and illustrate the diversity of psychopathological
phenomena and clinical states beyond the descriptions delivered by the diagnostic
systems, well aware that we are not writing textbook of psychiatry. Therefore, our
treatment of diagnostic and psychopathological issues is by no means exhaustive
but serves to emphasize aspects of special interest for differential diagnosis.
Furthermore, it should be stressed that our diagnostic principles are exclusively
based on clinical phenomena, not paraclinical procedures. Equally, we abstain from
giving etiological explanations and dynamic accounts of the psychopathological
processes, knowing that these always depend on a complex interaction of predisposing factors, environmental influences, subcultural and ethnic factors, psychological

reactions, coping strategies, etc. (cf. Birnbaums model for psychosis 1974). Factors
like these influence the case-specific variability and the meaningfulness of the psychopathological themes. But what matters most for the differential diagnosis is the
basic structure of psychopathology; explanatory theories must be left to subsequent
consideration and are beyond the scope of this book.
The first part of the book is devoted to the psychiatric diagnostic interview. The
concepts of validity and reliability are discussed in Chap. 2. These basic methodological concepts were among the central arguments in discussions concerning
nosological questions and the development of the polythetic diagnostic criteria, and
as we will argue, these concepts entail certain difficulties.
Chapter 3 analyzes the diagnostic interview, which is analyzed at a theoretical
level. We discuss the nature of symptoms and signs and the appropriate way of
examining them. Additionally, we provide a description of prototypes and the notion
of Gestalt and show that these are indispensable in the psychiatric diagnostic interview. Important aspects of the subject’s experiences to uncover in the process are
content, structure, and meaning relations to other experiences. Finally, we briefly
outline the phenomenological approach to the psychiatric interview.
Chapter 4 deals with the methodological and practical aspects of the interview.
We provide a thorough examination of the methodological approaches and the theories behind them and present a few empirical results. Further, we discuss the interviewer’s behavior and the rapport. We argue that empathy, here understood as the


1

Introduction

3

strong intention to comprehend the patient’s experience and existence, should permeate the interview. Finally, we offer some basic tips for the good interview and
illustrate some potentially difficult interviews.
Chapter 5 scrutinizes the importance of the appraisal of psychopathological
expressivity. In this chapter, there is a description of a variety of expressive phenomena and their relevance for differential diagnosis. The main groups of expressive
phenomena presented here are appearance and behavior; motor disturbances; catatonia; compulsions and pseudocompulsions; extrapyramidal side effects from antipsychotic medication; eye contact and gaze; rapport; mood; affect; speech and
language, and among these, formal thought disorders; cognition; and self-harm and

suicide. Aspects of the different expressive signs are illustrated in each section.
The second part of the book is dedicated to the psychopathological structure of
the diagnostic spectra. In the first chapter, Chap. 6, we introduce the very notion of
spectrum, a class of clinical conditions sharing the same basic structure in various
forms and degrees of severity. We believe that what is valid in psychiatric nosology
is the underlying psychopathological structure of these spectra (say the fundamental
symptoms of the schizophrenia spectrum and the basic affective moods) rather than
the actual formal criteria of the single diagnosis. Only after establishing the psychopathological affiliation to the spectrum in question, the specific diagnosis can be
made using these criteria.
In each of the following Chaps. 7, 8, 9, 10, 11, 12, and 13, we examine critically
the DSM-5 and ICD-10 diagnostic criteria for the principal diagnoses (in order to
counteract simplified popular readings) and go through the fundamental psychopathological structures of the spectrum, the patterns of diachronic course, the variations in clinical presentation (including subclinical cases), the borders of the
spectrum, and the differential diagnostic aspects of importance are summarized in
comparative tables. The order of these chapters follows, more or less, the diagnostic
hierarchy of ICD-10.
Chapter 7 on organic pathology first outlines the general characteristics of
organic mental states. Though naturally not constituting a coherent diagnostic spectrum, these states do, however, share some common features. Section 7.4 lists a
number of organic states mimicking functional mental illness and Sect. 7.5, the
other way around, some mental illness mimicking organic states.
Chapter 8 deals with psychosis. Section 8.1 makes an attempt to define psychosis
beyond the mere presence of “psychotic symptoms.” Near-psychotic phenomena
are described separately. Most of the chapter is about schizophrenia and the schizophrenia spectrum. That this is the most extensive chapter is motivated by the fact
that schizophrenia spectrum psychopathology is complex and multifarious and that
this spectrum is a major differential diagnostic area of hospital psychiatry. The basic
psychopathological structure of the schizophrenia spectrum is constituted by autism
and self-disorder.
Chapter 9 concerns depression and depressive-like states. Depression has become
a broad class of mental states characterized by agonizing distress. Most patients in
such a state of distress are at risk of being diagnosed with depression irrespective of
their underlying psychopathology. This chapter aims at dissecting this broad class

4

1

Introduction

into meaningful subcategories (core depression, reactive “paradepression,” and
pseudo-depression). Bipolar depression, a core depression, is treated here too,
whereas mania, hypomania, and mixed states are relegated to Sect. 11.1 devoted to
bipolar disorder. A specific quality of depressive mood is the essential structure of
core depression.
Chapter 10 covers anxiety states, another broad diagnostic category not belonging to a single diagnostic spectrum. First we try to pin down the major aspects of
anxiety, and then we focus on selected anxiety domains of importance for differential diagnosis, among these panic attacks, social anxiety, and obsessive-compulsive
states. Social anxiety, in the broad sense, a heterogeneous class of anxiety states on
its own, accompanies a whole range of different psychopathological conditions, and
obsessive-compulsive-like features seem omnipresent, too. Hypochondria as an
anxiety state has an important differential diagnosis of hypochondriac delusional
disorder, treated in this chapter, too, for convenience sake.
Chapter 11 brings into focus bipolar disorder (except bipolar depression treated
in Chap. 9) and other episodic nonorganic psychoses, including the acute psychoses. Mania often appears to be used as the designation of any acute psychosis with
motor agitation regardless of the quality of other psychopathological phenomena,
even in the absence of true manic mood. Therefore, we will focus on the basic structure of mania. The classification of acute non-affective psychoses differs according
to historical traditions. This chapter aims at defining and delimiting these states.
Chapter 12 treats of personality disorders (PD), which are considered dimensional rather categorical diagnoses, also reflected in the cluster structure of ICD-5
PD. Cluster A PD are related to the schizophrenia spectrum. Special attention is
devoted to borderline personality disorder, a widely used and misused diagnosis.
Borderline PD seems often, erroneously, to be allotted to patients characterized by
affective instability and self-harm, even in case of psychosis. We examine the differential diagnosis between personality disorder and other mental illness.

Chapter 13 touches upon aspects of adolescent psychiatry of significance for
adult psychiatry: premorbid traits, the early development of mental illness, and
diagnostic areas like the autism spectrum and ADHD.
In the last chapter (Chap. 14), the clinical interview for differential diagnosis is
put into the context of a broad diagnostic examination also comprising observation,
psychological testing, medical examination, and paraclinical tests, the full discussion of which is beyond the scope of this book. Throughout the book, we exemplify
many points by clinical vignettes. We are convinced that the semi-structured, conversational, and phenomenologically informed approach is the proper way to meet,
examine, and diagnose the psychiatric patient.
References in the empirical parts of the book were mainly selected according to
their clinical relevance and the standard of psychopathology communicated. Thus,
literature reflecting a qualitative, a descriptive, or a clinical, phenomenologicalanthropological approach has been preferred to empirical studies using structured
instruments. References to the diagnostic systems, not given in the next chapters,
are as follows: ICD-8 (World Health Organization 1965), ICD-10 (World Health
Organization 1992), DSM-II (American Psychiatric Association 1968), DSM-III


References

5

(American Psychiatric Association 1980), DSM-III-R (American Psychiatric
Association 1987), DSM-IV (American Psychiatric Association 1994), DSMIV-TR (American Psychiatric Association 2000), and DSM-5 (American Psychiatric
Association 2013).
This book mainly targets clinical psychiatrists and psychologists engaged in
diagnostics, but it also caters for researchers in need of refining their interviewing
skills and psychopathological definitions. Furthermore, we think that this book may
impart knowledge of psychopathology and differential diagnosis to psychiatry
workers and students not themselves involved in diagnostics.
Apart from interviewing skills and knowledge of the principles of differential
diagnosis, diagnostic skills also imply thorough theoretical and clinical knowledge

of psychopathology from reading psychiatric literature (preferably including preoperational continental classics), solid clinical experience, and personal supervision
and other kinds of feedback (e.g., obtained by attending formalized clinical interviews followed by peer discussions about the presented psychopathology). We will
especially emphasize the rewarding practice of discussing live and video-recorded
patient interviews among clinicians.
It is our hope that this book will encourage clinicians to take a renewed qualitative interest in psychopathology and diagnostics and that it will make a small contribution to changing the direction of clinical psychiatry from compulsively counting
symptoms to sincerely listening to the patient.
The authors wish to personally thank the following people for their contributions
in creating this book: Prof. Josef Parnas for his inspiration and constructive suggestions for the book, Prof. Louis Sass for his collaboration on the theory and methodology of the diagnostic interview, and the following persons for critically reviewing
parts of the manuscript and for contributing many helpful suggestions: Psych.
Birgitte Bechgaard, Dr. Lydia Damhave, Postdoc Mads Gram Henriksen, and
Dr. Annick Urfer Parnas.

References
American Psychiatric Association (1968) Diagnostic and statistical manual of mental disorders
(2nd ed.). Washington, DC
American Psychiatric Association (1980) Diagnostic and statistical manual of mental disorders
(3rd ed.). Washington, DC
American Psychiatric Association (1987) Diagnostic and statistical manual of mental disorders
(3rd ed., revised). Washington, DC
American Psychiatric Association (1994) Diagnostic and statistical manual of mental disorders
(4th ed.). Washington, DC
American Psychiatric Association (2000) Diagnostic and statistical manual of mental disorders
(4th ed., text rev.). Washington, DC
American Psychiatric Association (2013) Diagnostic and statistical manual of mental disorders
(5th ed.). Washington, DC
Birnbaum K (1974) The making of a psychosis. In: Hirsch NR, Shepherd M (eds) Themes and
variation in european psychiatry. University Press of Virginia, Charlottesville, pp 385–394
First M (2014) DSM-5™ handbook of differential diagnosis. American Psychiatric Publishing,
Arlington

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Introduction

Parnas J (2012) A sea of distress. In: Kendler KS, Parnas J (eds) Philosophical issues in psychiatry
II: nosology. Oxford University Press, Oxford, pp 229–233
Weitbrecht HJ (1966) Psychiatrische Fehldiagnosen in der Allgemeinpraxis. Fibel der
Differentialdiagnostik, Thieme
World Health Organization (1965) The ICD-8 Classification of Mental and Behavioural Disorders:
Clinical descriptions and diagnostic guidelines. Geneva
World Health Organization (1992) The ICD-10 Classification of Mental and Behavioural
Disorders: Clinical descriptions and diagnostic guidelines (blue and green book). Geneva


Part I
The Diagnostic Interview


2

Validity and Reliability

Abstract

Validity and reliability are central methodological concepts in psychiatric
nosology. However, the notion of validity raises considerable difficulties due to
the nature of psychiatric disorders. In this chapter, we discuss the two concepts,

their interrelation, and their shortcomings.
Good validity cannot be achieved without adequate reliability, but good
reliability does not necessarily ensure validity. Improved reliability of the
psychiatric diagnoses was paramount in the development of the operational
diagnostic criteria, but in the attempt to achieve this goal, validity was sacrificed.
Nonetheless, a striking improvement of the reliability of the clinical diagnoses
after the introduction of the operational systems (DSM-III+ and ICD-10) remains
to be seen.

In contemporary psychiatry, standardized, structured diagnostic interviews have
become the “gold standard,” especially in research but also increasingly in clinical
work. In Chaps. 3 and 4, we will challenge this assumption, but before doing so, it
is necessary to discuss some of the basic concepts involved when deciding between
tests. In our case, the “test” is the psychiatric diagnostic interview.

2.1

The Concept of Validity

The concept of validity is ambiguous; a variety of concepts are used to describe different facets of validity (each with indistinct boundaries), and the concepts describing them are not always used consistently (Rush et al. 2005). The adjective “valid”
is etymologically rooted in the Latin “validus” (literally meaning “strong” or
“robust”), which is derived from “valere” (literally meaning “to be strong”).

© Springer International Publishing Switzerland 2016
L. Jansson, J. Nordgaard, The Psychiatric Interview for Differential Diagnosis,
DOI 10.1007/978-3-319-33249-9_2

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Validity and Reliability

Although it is generally accepted that the validity of diagnostic categories concerns
the reality corresponding to each category, today there is no consensus about the
explicit meaning of the concept of validity. Generally, the concept of validity is
interwoven with a correspondence theory of truth, which is an epistemological position claiming that the truth or falsity of a belief is determined solely by whether or
not it actually corresponds to that which it describes in the real world. Another
theory of truth, perhaps more relevant for the current status of psychiatry, is the socalled coherence theory, which suggests that the truth or falsity of a belief is determined not by its correspondence to anything in the real world but only by its relation
to other beliefs in the particular belief system, i.e., whether or not it coheres with
these beliefs (Everitt and Fisher 1995). Both theories of truth entail, as any other
epistemological position, a number of philosophical problems. A classical objection
against the coherence theory is that it allows for a belief system being true, because
all of its beliefs cohere, even though each of the singular belief is in fact false. In
psychiatric research, psychopathological rating scales are usually validated against
each other, and if they concur, it is concluded that they are valid (or “true”). This
seems to be in accordance with the coherence theory. However, as already noted,
such agreement of coherence does not necessarily reflect anything about the real
nature of “what” is being rated. In other words, in spite of their coherence, they
could potentially all be measuring something else than the intended.
According to Schaffner, the validity concept is clearest in deductive logic, where
it refers to truth-preserving inference. In empirical science, the validity concept is,
as elicited in the description above, typically associated with capturing the objective, external “reality” (Schaffner 2012).
Obviously, there are several concepts of validity. In the following, we will only
sketch the more conventional concepts, namely, criterion, concurrent, predictive,
content, and construct validity:
“Criterion validity” refers to whether the measure agrees with a gold standard.

Criterion validity is the extent to which the measures are demonstrably related to
concrete features in the “real” world. When a gold standard or other criterion of
accuracy is available, a comparison with this standard is critical to assessing the
measure’s validity. Criterion validity is often divided into “concurrent validity” and
“predictive validity,” each of which has a specific purpose. “Concurrent validity”
refers to the agreement among two or more different measures, which hypothetically measure the same thing. For example, one set of diagnostic criteria for schizophrenia could be statistically analyzed against another set of diagnostic criteria for
schizophrenia; if there is a high correlation between the two sets of criteria, then the
concurrent validity is high. “Predictive validity” of a test instrument or a measurement tool is established by demonstrating its ability to predict the results of an
analysis of the same data provided by other test instruments or measurement tools.
This compares the measure in question with an outcome assessed at a later time, for
example, use of the grades from high school to predict grades in a future exam.
“Content validity” is a nonstatistical type of validity that involves a systematic
examination of the test (or diagnostic category) content to determine whether it covers a representative sample of the behavior domain measured (e.g., does an IQ


2.1

11

The Concept of Validity

questionnaire have items covering all areas of intelligence discussed in the scientific
literature?). Content validity also involves the degree to which the content of the test
matches the content domain associated with the construct (e.g., a test of the ability
to add two numbers should include a range of combinations of digits). A test has
content validity built into it by careful selection of which items to include.
“Construct validity” refers to the extent to which a test actually measures what
the theory says it does (e.g., to what extent is an IQ questionnaire actually measuring intelligence?). Construct validity involves empirical and theoretical support for
the interpretation of the construct (Anastasi and Urbina 2010).
It should be noted that various textbooks do not fully agree about these definitions, that the concepts to some extent overlap, and, moreover, that the distinction

between these concepts is not clear.

Box 2.1 Different Kinds of Validity
Criterion validity
(a) Concurrent validity
(b) Predictive validity
Content validity
Construct validity

Do the measures agree with a gold standard?
Do the measures’ results agree with other measures that are
hypothesized to measure the same phenomenon?
The measure’s ability to predict the correct result
Is the content representative for what it is being measured?
Does the test measure what it is constructed to measure?

When evaluating the validity of a diagnostic test, two important statistical measures are sensitivity and specificity. The sensitivity of a certain test indicates the
percentage of those with the disorder who are correctly classified, and, consequently, a diagnostic test with high sensitivity has few false negatives. The specificity, on the other hand, indicates the percentage of those without the disorder who are
correctly classified, and thus, a diagnostic test with high specificity has few false
positives (American Psychiatric Association 2000). Obviously, an ideal diagnostic
test scores 100 % in the domains of both sensitivity and specificity.

2.1.1

Validity of Allocating Psychiatric Diagnoses

Looking more specifically at the validity of allocating psychiatric diagnoses, Robins
and Guze suggested an approach to facilitate the development of valid classification
in psychiatry in 1970. Their approach became very influential and consisted of five
phases: (1) clinical description, (2) laboratory studies (including psychological

tests, radiology, and postmortem findings), (3) delimitation of the mental disorders
(similar clinical features may be seen in patients suffering from different disorders,
making exclusion criteria necessary), (4) follow-up studies to determine if there are
marked differences in the patients’ outcomes (instability of the patients’ diagnoses


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Validity and Reliability

indicates that the category might not be valid), and (5) family studies (higher prevalence of the disorder among close relatives of the patient indicates a valid category).
Obviously, the five phases interact with each other so that new findings in any one
of the phases may lead to modifications in one or more of the other phases (Robins
and Guze 1970).
The criteria of Robins and Guze have since been expanded by others, and
some of the external validators currently considered pertinent for psychiatric
disorders include family history, demographic correlates, biological and psychological tests, environmental risk factors, concurrent symptoms (that are not
a part of the diagnostic criteria being assessed), treatment response, diagnostic
stability, and course of illness (Kendler 1980, 1990). However, this approach
also gives rise to some considerations: it is implicitly assumed that different
external validators cohere (see coherence theory in Sect. 2.1), but there is no
theoretical argument for why this necessarily should be the case. Just because
course and outcome indicate that one set of criteria is superior to another set of
criteria, it does not necessarily imply that biological or demographic validators
will indicate something similar. In the situation of disagreement between validators, what validator is then the more valuable? Empirical methods alone cannot decide which validator should be given priority (Kendler 1990). Another
implicit assumption is that psychiatric disorders are discrete entities, and the
possibility that these disorders might merge into one another with no natural
boundary in between was simply not considered (Kendell and Jablensky 2003).

Consequently, a useful validating criterion must have both high sensitivity and
high specificity. Kendler makes it tangible with the following description:
“Although the criterion of familial aggregation probably has high sensitivity (all
evidence shows that psychiatric disorders run in families), the specificity is low
because many characteristics that run in families are not valid diagnostic entities, e.g., hair color, height and nose size” (Kendler 2006).
Different diagnostic criteria do not necessarily point in the same direction, as
illustrated in the study of Jansson et al. Comparing ICD-10 with ICD-9 diagnoses
they showed that out of a first-admission sample of 155 patients suspected of a
schizophrenia spectrum disorder, 89 received an ICD-9 schizophrenia diagnosis,
whereas only 35 patients from the same sample received an ICD-10 diagnosis of
schizophrenia. The ICD-10 patients with schizophrenia tended to be more frequently male, and the first psychiatric symptoms appeared earlier in life among
ICD-9 patients with schizophrenia. The ICD-9 schizophrenia status was associated
with nearly fourfold and statistically significant risk for having a positive family
history of schizophrenia (Jansson et al. 2002).
The validity criterion of outcome has proven less useful, as it has been demonstrated that some patients with schizophrenia recover completely and some bipolar
patients have a chronic and disabling course. Psychopharmacological treatments
also contribute to blur the picture resulting in massive “grey areas” of outcomes
(Jablensky 2012).
There is probably no simple measure of the validity of a diagnostic concept. The
types of validity often mentioned in the context of psychiatric diagnoses (i.e.,


2.2

The Concept of Reliability

13

construct, concurrent, content, and predictive) are all borrowed from psychometric
theory in psychology. However, only a few diagnostic concepts in psychiatry meet

these criteria at the level of stringency normally required of psychological tests
(ibid.).
The idea in the diagnostic classification is to form categories for ordering and
naming the disorders. In biology, the classifications reflect fundamental properties
of biological systems and constitute “natural” classifications. The position in psychiatric classification is quite different from that as the objects being classified in
psychiatry are not “natural” entities, but rather explanatory constructs (Jablensky
2012). A ‘natural kind’ is a family of entities possessing properties bound together
by natural law (e.g. minerals, plants or animals). This is in contrast to entities
lumped together by humans.
Believing that psychiatry will reach the same etiopathogenic validity that can be
seen in somatic medicine seems naïve given that the etiology of most psychiatric
disorders is multifactorial, meaning that the development of mental disorders is
influenced by many different psychopathological processes (Kendler and Parnas
2012). Further, a variety of etiological factors may produce the same syndrome,
implying that the relation between etiology and clinical syndrome is indirect
(Birnbaum 1974).
Frequently used phrases, such as a specific psychiatric scale “is well validated”,
often refer to concurrent validity. But, in many cases, this is actually an overestimation of the concurrent validity given that it is not known, e.g., what schizophrenia
really is or who the “true” schizophrenics are (Andreasen 2007). Inevitably, this
weakens the explanatory power of this concept.

2.2

The Concept of Reliability

Reliability is another important issue in the methodology of the psychiatric diagnostic interview. Reliability refers to consistency and repeatability (Rush et al. 2005),
i.e., to what extent does a diagnostic test produce the same results? Is it stable over
time and among different raters? Good validity is not achieved without good reliability. However, reliability can be excellent even though the validity is poor.
Reliability is often tested statistically by Cohen’s kappa. However, there is no
consensus about the interpretation of kappa. We have seen changing or different

interpretations of the kappa values, e.g., Spitzer and Fleiss (1974) interpreted
kappa below 0.70 as unacceptable (Spitzer and Fleiss 1974), Landis and Koch
(1977) considered kappas above 0.75 as being excellent (Landis and Koch 1977),
and Clarke and colleagues found kappas above 0.4 as good to excellent (Clarke
et al. 2013).
The relation between validity and reliability is often a trade-off. Generally, a
diagnostic criterion will be more reliable if it is explicit and if minimal inference is
required to assess its presence. However, restricting the criteria to those that can be
measured with low inference may endanger the validity. How to balance the importance of reliability versus validity in assessing the value of diagnostic criteria?