• Diagnosis = the classification of disorders by symptoms or signs o Advantages: facilitates communication among professionals, advances the search for causes & treatments, cornerstone of clinical care
  • Diagnosis can be the first major step in good clinical care
  • Correct diagnosis allows the clinician to describe base rates, causes, and treatment
  • Diagnosis helps a person understand why symptoms are occurring
  • Use assessment procedures to make a diagnosis (e.g. clinical interview)

Cornerstones of Diagnosis and Assessment

  • Reliability and validity are the cornerstones of any diagnostic or assessment procedure

Reliability

  • Reliability = consistency of measurement
  • Interrater reliability = the degree to which 2 independent observers agree on what they have observed
  • Test-retest reliability = measures the extent to which people being observed twice or taking the same test twice (after a period of break) receive similar scores o Makes sense to use when we can assume people won’t change of the target variable appreciably between sessions
  • Alternate-form reliability = the extent to which scores on two forms of a test are consistent
  • Internal consistency reliability = assesses whether the items on a test are related to one another  Reliability is measured on a scale from 0 to 1.0 (higher number = better reliability)

Validity

  • Validity = index of whether a measure measures what it is supposed to measure
  • Validity is related to reliability, unreliable measures will not have good validity  Reliability does not guarantee validity
  • Content validity = whether a measure adequately samples the domain of interest o g. social anxiety measure should have items covering feelings of anxiety in social situations
  • Criterion validity = evaluated by determining whether a measure is associated in an expected way with some other measure (the criterion) o Concurrent validity = both variables are measured at the same point in time

 E.g. showing that a measure of negative thoughts is associated with a measure of depression symptoms

  • Predictive validity = the ability of the measure to predict some other variable that is measured at some point in the future
    • g. IQ tests to measure future school performance
  • Construct validity = used to interpret a test as a measure of some characteristic/construct that is not observed overtly o g. people score differently on a measure for anxiousness actually do differ in degree of that construct
    • Evaluated by looking at a wide variety of data from multiple sources o Related to theory

The Diagnostic System of the American Psychiatric Association: DSM-5

  • The Diagnostic and Statistical Manual of Mental Disorders o USA uses International Classification of Disorders – 10
  • Revised 5 times since 1952  DSM-5 released in 2013  Introduced in DSM-III:
    • Specific diagnostic criteria *symptoms for a given diagnosis
    • The characteristics of each diagnosis are described much more extensively

Changes in DSM-5

  • Removal of the Multiaxial System:
    • DSM-IV-TR had 5 axes, changed to 2 (or 3) in DSM-5 *clinical syndromes & psychosocial & environmental problems
    • First developed in DSM-III (1980) o In place of first 3 axes, clinicians now note psychiatric and medical diagnoses o Psychosocial and Environmental Problems Axis changed to be similar to the WHO

International Classification of Diseases (ICD) o Axis 5 is removed, instead the WHO Disability Assessment Schedule (WHODAS) is included  Organizing Diagnoses by Causes:

  • Defines diagnoses on the basis of symptoms (DSM-IV)
  • Chapters are reorganized to reflect patterns of comorbidity and shared etiology (DSM-5)  OCD moved from anxiety cluster to new cluster that also includes hoarding and body dysmorphic disorder
  • Enhanced Sensitivity to the Developmental Nature of Psychopathology:
    • Highlights the continuity between childhood and adulthood forms of disorder o No separate chapter for childhood disorders
  • New Diagnoses:
    • g. disruptive mood dysregulation disorder (mood changes, irritability and mania symptoms) o Often incorrectly diagnose these patients with bipolar although they do not correctly fit the diagnosis for mania
    • Hoarding disorder, binge eating disorder, premenstrual dysphoric disorder, gambling disorder  Combining Diagnoses:
    • Not enough evidence for differential etiology for certain disorders o Substance use disorder (instead of substance abuse and dependence) Female sexual interest/arousal disorder (instead of hypoactive sexual desire disorder and female sexual arousal disorder)
    • Autism spectrum disorder (autism and Asperger’s)  Ethnic and Cultural Considerations:
    • Many different cultural influences on risk factors for certain psyc disorders, symptoms experienced, willingness to seek help, treatments available
    • DSM-5 includes a list that cross-references the DSM diagnoses with the International

Statistical Classification of Diseases and Related Health Problems (ICD) codes o Added features to enhance cultural sensitivity o Includes a section on culture-related diagnostic issues

  • Clinicians are cautioned not to diagnose symptoms unless they are atypical and problematic within a person’s culture
  • Includes 9 cultural concepts of distress
    • Dhat syndrome – (India) severe anxiety about the discharge of semen
    • Shenjing shuairuo – (China) syndrome characterized by fatigue, dizziness, headaches, pain, poor concentration, sleep problems and memory loss
    • Taijin kyofusho – (Japan) fear that one could offend others through inappropriate eye contact, blushing, perceived body deformation, one’s own foul body odor
    • Ataque de nervios – (Latino culture) intense anxiety and fear of screaming and shouting uncontrollably

Specific Criticisms of the DSM  Too Many Diagnoses?

  • Contains more than 300 different diagnoses
  • Seems as though too many problems have been made into psyc disorders o Some argue that the system includes too many minute distinctions based on small differences in symptoms
  • Classification may emphasize trivial similarities  relevant info may be overlooked o Comorbidity = the presence of a second diagnosis *norm rather than the exception
    • Could be a sign that we are dividing syndromes too finely
    • 45% of people diagnosed with 1 disorder will meet criteria for a second disorder o Many risk factors seem to trigger more than one disorder
  • Why not lump childhood conduct disorder, adult antisocial personality disorder, alcohol use disorder, and substance use disorder into “externalizing disorders”
  • Research Domain Criteria = roadmap for research that will lead to the development of a new classification system that is based on neuroscience and genetic data rather than just clinical symptoms
  • Categorical Classification Versus Dimensional Classification:
    • Categorical classification = classification requiring the presence of a certain amount of specific symptoms that fall under a diagnosis category (DSM-5)
      • Forces clinicians to define one threshold as “diagnosable” o Dimensional system = describes the degree of an entity that is present
      • Dimensional approach for personality disorders is included in the appendix o Unspecified – used when a person meets many but not all of the criteria for a diagnosis  Used to be called NOS
    • Reliability of the DSM in Everyday Practice:
      • Reliability for diagnosis was poor prior to DSM-III
      • Difficult for mental health professionals to always agree on a diagnosis
    • How Valid Are Diagnostic Categories?
      • DSM diagnoses are based on a pattern of symptoms
      • We hope a diagnosis will inform us about related clinical characteristics and functional impairments
      • Impairment or distress must be present to meet criteria for diagnosis
      • We hope a diagnosis will inform us what to expect next (course of disorder, response to treatment options)

General Criticisms of Diagnosing Psychological Disorders

  • Getting a diagnosis could have a stigmatizing effect
  • Family members often also encounter a stigma
  • People tend to view the actual disordered behaviour more negatively than the category labels  Lose sight of personal uniqueness once a diagnosis is applied

Psychological Assessment

  • Using multiple techniques and multiple sources of info will provide the best assessment

Clinical Interviews

  • Both formal/structured and less structured clinical interviews  Characteristics:
    • Interviewer pays attention to how the respondent answers questions, or doesn’t answer
      • Look for emotion that accompanies responses o Establish rapport with the individual, obtain their trust, empathize
    • Interviewer must rely on intuition and general experience to figure out how best to gather information
    • Unstructured interviews are less reliable than structured  Structured Interviews:
    • Structured interview = questions are set out in a prescribed fashion for the interviewer
      • g. the Structured Clinical Interview (SCID), being revised for DSM-5
      • A person’s response to one question determines what the next question will be = branching interview
      • Gives instructions as to when to go into more detail and when to move on
      • Most symptoms rated on a 3-point scale of severity o Clinicians using unstructured diagnostic interviews tend to miss comorbid diagnoses

Assessment of Stress

  • Stress = the subjective experience of distress in response to perceived environmental problems  Life stressors = the environmental problems that trigger the subjective sense of stress  The Bedford College Life Events and Difficulties Schedule (LEDS):
    • Includes an interview that covers over 200 different kinds of stressors o Semi-structured interview o Designed to address a number of problems in life stress assessment o Goal to exclude life events that might just be consequences of symptoms o Tries to carefully date when a stressor has occurred
    • Life stressors are robust predictors of episodes of anxiety, depression, schizophrenia and even the common cold
  • Self-Report Stress Checklists:
    • Quicker method of assessing stress
    • g. the List of Threatening Experiences (LTE) or the Psychiatric Epidemiological Research Interview Life Events Scale

List different life events, participants are asked to indicate whether or not these events happened to them in a specified period of time

  • Issue: high variability in how people view these events o Issue: difficulties with recall o Low test-retest reliability Personality Tests:
  • 2 most common types of psyc tests: personality tests & intelligence tests  Self-Report Personality Inventories:
    • Personality inventory = the person is asked to complete a self-report questionnaire including whether statements assessing habitual tendencies apply to him/her
    • Administered to analyze how certain kinds of people tend to respond o Standardization = process of establishing statistical norms for a test
    • Minnesota Multiphasic Personality Inventory (MMPI) = designed to detect a number of psyc problems based on responses to certain items in a similar manner as individuals with a particular diagnosis
      • MMPI-32 is much more reliable, has adequate criterion validity
      • Specific subscale to detect lying & faking “good”/”bad”  Projective Personality Tests:
    • Projective test = a psych assessment tool in which a set of standard stimuli

(inkblots/drawings) ambiguous enough to allow variation in responses is presented to the person

  • Because the stimulus materials are unstructured/ambiguous, the person’s responses will be determined by unconscious processes and will reveal true attitudes/motivations =projective hypothesis
  • Used when the subject is assumed to be unwilling or unable to express true feelings in asked directly
  • Thematic Apperception Test (TAT) = a person is shown a series of black and white pictures

1@ a time, and asked to tell a story related to each

  • Not very reliably scored, low construct validity o Rorschach Inkblot Test = person is shown 10 inkblots, one at a time, and asked to tell what the inkblots look like *most well-known
  • Exner scoring system, concentrates on perceptual and cognitive patterns in a person’s responses
  • Responses viewed as a sample of how subject perceptually/cognitively organizes reallife situations
  • Norms of this scoring system based on a small sample
  • Validity with assessing certain issues, not with others Intelligence Tests
  • Alfred Binet
  • Intelligence test (IQ) = used to assess a person’s current mental ability
  • Based on the assumption that a detailed sample of a person’s current intellectual functioning can predict how well he/she will perform in school
  • Most common: Wechsler Adult Intelligence Scale & Stanford-Binet  Regularly updated and standardized  Other uses:
    • Diagnose learning disorders and identify areas of strength/weakness o Assess whether a person has intellectual disability

 

Identify intellectually gifted children o Part of neuropsychological evaluations

  • Tap: language skills, abstract thinking, nonverbal reasoning, visual-spatial skills, attention/concentration, speed of processing
  • 100 is often the standardized mean (15 or 16 = SD)
  • Highly reliable, good criterion validity
  • IQ tests explain only a small part of school performance
  • IQ is also correlated with health
  • Stereotype threat (stigma towards some groups for poor intellectual performance)

Behavioural and Cognitive Assessment

  • Assess: aspects of the environment, characteristics of a person, frequency/form of problem behaviours, consequences of problem behaviour  Direct Observation of Behaviour:
    • Observer divides sequence of behaviour into various parts that make sense within a learning framework (e.g. antecedents, consequences)
    • Behavioural assessment = observing behaviour and coding it  Self-Observation:
    • Self-monitoring = patients observe and track their own behaviour and responses
      • Used to collect wide variety of data (moods, stressful experience, coping behaviour, thoughts)
    • Ecological momentary assessment (EMA) = collection of data in real time (rather than reflecting back), a person is signaled several times a day, asked to enter responses directly into device
    • Behaviour can be altered by the mere fact that it is being self-monitored = reactivity  Cognitive-Style Questionnaires:
    • Used to help plan targets for treatment and to determine whether clinical interventions are helping
    • Dysfunctional Attitude Scale (DAS) *based on Beck’s theory

Neurobiological Assessment

Brain Imaging: “Seeing” the Brain **used less frequently (expensive)

  • Neurological tests: checking reflexes, examining the retina, evaluating motor coordination/perception
  • CT/CAT scan (computerized axial tomography) = x-rays pass into horizontal cross section of brain, scanning it through 360 degrees, scanner on other side measures radioactivity that penetrates o Detects subtle differences in tissue density o Constructs a 2D, detailed image of cross-section
    • Reveals structural abnormalities by detecting differences in tissue density (e.g. enlarged ventricles)
  • MRI (magnetic resonance imaging) = produces pictures of higher quality than CT, does not rely on radiation o Person placed inside a large magnet, causes H atoms of body to move
  • fMRI (functional MRI) = allows researchers to measure brain structure and function o Quick pictures allow metabolic activity to be measured
    • Measures blood flow in the brain = BOLD signal (blood oxygenation level dependent) o As neurons fire, blood flow increases
  • PET scan (positron emission tomography) = more expensive and invasive, allows measurement of brain structure and function, not as precise as MRI/fMRI

Radioactive isotope injected into bloodstream, binds to glucose o Red = most activity, blue/black = least activity *used less often

  • Functional connectivity analysis = tries to identify deficits in the ways in which different areas of the brain communicated and connect with one another

Neurotransmitter Assessment

  • Post mortem studies
  • Bind receptors in deceased patients to detect amount of certain receptors in the brain
  • Metabolite assays = an acid/by-product that is produced when a neurotransmitter is deactivated o Often found in urine, blood serum, and cerebrospinal fluid
    • Not direct reflections of neurotransmitter levels in the brain (blood and urine)
  • Metabolite studies are correlational *not always accurate

Neuropsychological Assessment

  • Neurologist = a physician who specializes in diseases/problems that affect the nervous system o g. stroke, muscular dystrophy, cerebral palsy, Alzheimer’s
  • Neuropsychologist = a psychologist who studies how dysfunctions of the brain affect the way we think, feel, and behave
  • Neuropsychological tests = used with brain imaging to detect brain dysfunction and to help pinpoint specific areas of behaviour that are impacted by problems in the brain  Based on idea that different psyc functions rely on different areas of the brain  Halstead-Reitan neuropsychological test battery (group of tests):
    • Tactile performance test-time = while blindfolded, person tries to fit differently shaped blocks into spaces of a form board, using the preferred hand, than the other, then both
    • Tactile performance test-memory = person asked to draw the form board from memory, showing blacks in their proper location
      • Both above 2 are sensitive to damage in parietal lobe o Speech sounds perception test = participants listen to series of nonsense words, each made of 2 consonants with a long-e sound in the middle, then select the “word” they heard from a set of alternatives
      • Measures left-hemisphere function *temporal and parietal areas
    • Luria-Nebraska battery – 269 items, 11 sections, determine basic/complex motor skills, rhythm and spatial abilities, tactile and kinesthetic skills, verbal and spatial skills, receptive speech ability… o Helps reveal potential damage in frontal, temporal, sensorimotor, or parietal-occipital area of either hemisphere
      • Reliable scoring, can control for educational level

Psychophysiological Assessment

  • Psychophysiology = concerned with the bodily changes that are associated with psychological events
  • Measure heart rate, muscle tension, blood flow, electrical activity in brain
  • Not sensitive enough to be used for diagnosis
  • Assess activity of ANS to understand emotion
  • Electrocardiogram (EKC) = measures electrical charge generated by heartbeat
  • Electrodermal responding = skin conductance *sympathetic NS *sweat gland activity
  • Electroencephalogram (EEG) = measures brain activity using electrodes on the scalp o Abnormal patterns can indicate seizure activity, help locate lesions or tumors o Used to measure attention and alertness

A Cautionary Note About Neurobiological Assessment

  • Many measurements do not differentiate clearly among emotional states o g. skin conductance increases with many emotions
  • Being in a scanner can generate anxiety on its own, it’s a scary experience

Cultural and Ethnic Diversity and Assessment Cultural Bias in Assessment

  • A measure developed for one culture/ethnic group may not be equally reliable and valid with a different group **not simply a matter of language translation
  • Cultural assumptions/biases may cause clinicians to over/under estimate psyc problems

Strategies for Avoiding Cultural Bias in Assessment

  • Students need to learn how culture/ethnicity may impact assessment
  • But that it may not impact assessment in every individual case