1d: Clinical Diagnosis copy

Diagnosis

  • not a single decision made at one point in time

  • a broader process

Engagement

  • Patient Experiences a Health Problem

    • Patient engages with the health care system through a diagnostic process.

  • Diagnostic Process Assessment

    • Gathering information from multiple sources:

    • Clinical History and Interview

    • Referral and Consultation

    • Physical Exam

    • Diagnostic Testing

  • Communication of the Diagnosis

    • Explanation of the health problem communicated to the patient.

  • Intervention

    • The planned path of care based on the diagnosis.

Outcomes

  • Patient and System Outcomes

    • Learning from diagnostic errors, near misses, and accurate, timely diagnoses.

Making a Diagnosis

  • Signs: Observable characteristics that accompany a disorder (e.g., flat affect, sleep difficulties).

    • we can see or measure

  • Symptoms: Subjective experiences that accompany a disorder (e.g., worry, hopelessness, hallucinations).

  • Syndrome: A cluster of signs and symptoms that commonly co-occur (e.g., panic attacks, anxiety, hyperventilation, tension).

    • signs + symptoms

  • Assumptions of the Medical Model:

    • Classifying abnormal behavior caused by underlying pathological processes.

Purpose of a Diagnosis

A diagnosis aims to:

  1. Describe

    • Cause

    • Behavior (clinical characteristics and functional impairment)

    • Prediction (e.g., marital distress)

    • possible underlying mechanisms

  2. Communicate

    • can communicate clearly with other including the patient

  3. Legitimise

    • recognises patient experience in a formal system

  4. Research

Diagnostic Classification Systems

  • International Statistical Classification of Diseases and Related Health Problems (ICD)

    • Originally created in 1900.

    • Morbidity added in 1948.

    • Currently in its 11th edition (2018).

  • Diagnostic and Statistical Manual of Mental Disorders (DSM)

    • Kraepelinian dichotomy of psychosis:

    • Manic depression

    • Dementia praecox

    • Originally published in 1952, currently the 5th edition (2013).

The Current Diagnostic System

  • Definition (American Psychiatric Association, 2013, p.20):

    • “A mental disorder is a syndrome characterized by clinically significant disturbance in an individual’s cognition, emotion regulation, or behavior that reflects a dysfunction in the psychological, biological, or developmental processes underlying mental functioning. Mental disorders are usually associated with significant distress or disability in social, occupational, or other important activities. An expectable or culturally approved response to a common stressor or loss, such as the death of a loved one, is not a mental disorder. Socially deviant behaviors (e.g., political, religious, or sexual) and conflicts that are primarily between the individual and society are not mental disorders unless the deviance or conflict results from a dysfunction in the individual, as described above.”

Major DSM-5 Mental Disorders

  • Categories:

    • Neurodevelopmental/Elimination

    • Neurocognitive

    • Substance-Related and Addictive Disorders

    • Schizophrenia Spectrum and Other Psychotic Disorders

    • Bipolar and Related Disorders

    • Depressive Disorders

    • Anxiety Disorders

    • Obsessive-Compulsive and Related Disorders

    • Trauma and Stressor-Related Disorders

    • Dissociative Disorders

    • Somatic Symptoms and Related Disorders

    • Sexual/Gender/Paraphilic Disorders

    • Feeding and Eating Disorders

    • Sleep-Wake Disorders

    • Disruptive/Impulse-Control and Conduct Disorders

    • Personality Disorders

  • Specificities and exclusions for diagnosis:

    • Causes clinically significant distress or impairment.

    • Not due to medical condition or substance.

Advantages of Diagnosis

  • Advances the search for causes.

  • Guides treatment selection.

  • Reliability of assessment.

  • Communication between individual and health professionals.

  • Cornerstone of clinical care.

  • provides shared language

Issues in Diagnosis and Classification

  • Concerns:

    • diagnosis is socially constructed

    • Labels, stigma, and discrimination

    • Overlooks the lived experience

    • Common underlying processes

    • Decision making

    • Categorical vs. dimensional

    • Sensitivity and specificity

    • Reliability and validity

    • Comorbidity complicates classification

Decision Making in Diagnosis

  • False Positives: Occur when one identifies or predicts a situation (like a diagnosis) incorrectly.

    • diagnose a disorder not present

  • False Negatives: Occur when one incorrectly identifies a condition as absent.

    • fail to identify a disorder present

    • especially serious, may miss out on treatment needed for a disorder present

    • hence, sensitivity is crucial for diagnostic tools

Sensitivity and Specificity

  • Sensitivity (True Positive Rate):

    • True State (Person has schizophrenia):

    • HIT

    • FALSE POSITIVE

    • True State (Person does not have schizophrenia):

    • FALSE NEGATIVE

    • TRUE NEGATIVE

  • Specificity (True Negative Rate): Measures the accuracy in identifying those without the disorder.

Categorical vs. Dimensional Approaches

  • Categorical:

    • Disorders are distinct; e.g., Major Depression differs from schizophrenia.

    • Presence/absence of a disorder is binary, either anxious or not.

    • approach supports strucutre and communication

    • oversimplifies experience

  • Dimensional:

    • Ranks symptoms on a continuous quantitative dimension.

    • Example: Degree of a symptom on a scale of 1 to 10.

    • there’s a threshold for diagnosis (e.g. scale 0-10, threshold is 5)

    • considerable variety across population

Moving Towards a Dimensional Approach

  • Asks if abnormality presents in degrees.

  • Differing models of classification include:

    • Categorical vs. dimensional (e.g., depressed mood).

  • Considers degrees of sadness and types of depression with varying degrees (e.g., reactive vs. clinical depression).

Comorbidity (simultaneous presence of 2+ conditions) in Diagnosis

  • Diagnostic Overlap:

    • E.g., Generalized Anxiety Disorder (GAD) and Major Depressive Disorder (MDD) share overlapping symptoms.

  • Statistics on prevalence:

    • Two disorders: 22%

    • Three disorders: 3%

    • One disorder: 75%

  • do diagnostic categories represent truly distinct conditions?

  • or does it represent partially overlapping processes

Reliability and Validity in Assessment

  • Inter-Rater Reliability:

    • Extent to which clinicians agree on a diagnosis.

  • Test-Retest Reliability:

    • Consistency of diagnosis over time with the same signs and symptoms.

    • Generally good for most DSM categories but may be lower in real-world settings than in research.

Beyond Categorical Diagnosis

  • Need for Alternative Frameworks:

    • To provide insights on why, how, and what behaviors present.

    • under a pure categorical framework, some patients may not qualify for a diagnosis

  • Focus on:

    1. Severity of distress rather than all-or-nothing categories.

    2. Psychological processes underlying distress across diagnoses.

    3. Individual experiences, social context, and meaning-making shaping responses to threat.

Dimensional Framework

  • Understanding Psychological Distress:

    • Exists along continum of severity, not as absolute categories.

    • Mental health difficulties vary in degree rather than kind.

    • Captures meaningful distress without meeting diagnostic thresholds.

  • addresses Limitations of Categorical Diagnosis:

    • Symptoms are rarely simply present or absent; intensity, frequency, and impact vary across individuals.

    • Focus moves from “Does this person meet criteria?” to “How severe is the distress and how does it affect functioning?”

Dimensional Framework in Practice

  • Useful when:

    • Individuals remain highly functional.

    • They compare themselves to worse cases and believe they don’t need help.

  • Used alongside diagnosis for:

    • Access to services.

    • Formulation, treatment planning, risk assessment, and monitoring change.

Transdiagnostic Framework

  • Focus on Shared Psychological Processes:

    • Examines mechanisms that maintain distress rather than categories.

    • Developed in response to high comorbidity and overlapping criteria of disorders.

    • Suggests that many disorders reflect common underlying processes rather than distinct conditions.

Transdiagnostic Processes Identified

  • Common across cognitive, behavioral, and stress-based models:

    • Heightened threat sensitivity.

    • Avoidance behaviors.

    • Emotion regulation difficulties.

    • Maladaptive beliefs.

    • Attentional biases.

    • Stress reactivity.

Power, Threat and Meaning (PTM) Framework

  • Characteristics:

    1. Focus on purposeful human behavior in social contexts rather than bodily processes.

    2. Abnormal behaviors exist on a continuum with normal behaviors.

    3. Emotional distress is mediated by biological, social, and cultural contexts.

    4. Meaning, narratives, and subjective experiences are crucial.

  • alternatives to diagnosis need to focus on humans behaving purposeful in social and relational contexts (not on bodily processes or objects in the world)

  • abnormal behaviours exists on a continuum with normal behvaiour

  • experiences of emotinoal distress are enabled or mediated by biology

  • humans are fundamentally social beings whose experience of distress are inseparable from contexts

  • need to take meaning, narrative and subjective experience seriously

  • Key Questions PTM Asks:

    • Instead of:

    • “What is wrong with you?”

    • “What problems are you having?”

    • “What distress are you experiencing?”

    • It asks:

    • “What happened to you?” (Power)

    • “How did it affect you?” (Threat)

    • “What sense did you make of it?” (Meaning)

    • “What did you do to survive/cope?” (Threat Response)

Case Study: Alex

  • Profile:

    • 33-year-old professional with chronic sleep difficulties, irritability, tension, and avoidance of social events.

    • Experiences persistent feelings of being “on edge” following workplace pressure and relationship breakdown.

    • Avoidant of seeking help due to perceived functional status.

  • Dimensional Framework Application:

    • Symptoms vary in intensity and impact.

    • Functional status does not negate clinically meaningful distress.

  • Transdiagnostic Framework Application:

    • Explores shared mechanisms contributing to Alex's distress and avoids categorical labeling.

  • PTM Framework Application:

    • Contextualizes Alex's experiences and tailors understanding to their individual narrative.

Summary

  • Categorical Models:

    • Prioritize reliability and structure but risk oversimplification.

  • Dimensional Models:

    • Capture severity and variability but are harder to implement in structured systems.

  • Comorbidity:

    • Challenges distinctness of diagnostic categories.

  • Transdiagnostic Frameworks:

    • Focus on shared psychological mechanisms across disorders.

  • Power Threat and Meaning:

    • Reframes distress as meaningful and contextual rather than purely pathological.

  • Understanding differences among these approaches:

    • Essential for critically evaluating modern diagnosis in psychology.