Diagnosis and assessment - summary of chapter 3 of Abnormal Psychology by Kring, Davison, Neale & Johnson (12th edition)

Clinical psychology 
Chapter 3
Diagnosis and assessment

Introduction

Diagnosis can be the first major step in good clinical care.
Having a correct diagnosis will allow the clinician to describe base rates, causes, and treatment.
Hearing a diagnosis can help a person understand why certain symptoms are occurring.

Two concepts that play a key role in diagnosis and assessment:

• Reliability
• Validity

Cornerstones of diagnosis and assessment

Reliability

Reliability: consistency of measurement.

• Inter-rater reliability:
  The degree to which two independent observers agree on what they have observed.
• Test-retest reliability:
  The extent to which people being observed twice or taking the same test twice, receive similar scores.
• Alternate-form reliability:
  The extent to which scores on the two forms of the test are consistent
• Internal consistency reliability:
  Whether the items on a test are related to one another.

Validity

Validity: whether a measure measures what it is supposed to measure.
Unreliable measures will not have good validity.
Reliability does not guarantee validity.

• Content validity:
  Whether a measure adequately samples the domain of interest.
• Criterion validity:
  Whether a measure is associated in an expected way with some other measure.
• Concurrent validity: 
  If both variables are measured at the same point in time.
• Predictive validity:
  Evaluating the ability to measure to predict some other variable that is measured at the same point in the future.
• Construct validity:
  Relevant when we want to interpret a test as a measure of some characteristic or construct that is not observed simply or overtly. Evaluated by looking at a wide variety of data from multiple sources.

The diagnostic system of the American psychiatric association: DSM-5

Diagnostic and Statistical Manual of Mental Disorders (DSM).

Multiaxial classification system forces the diagnostician to consider a broad range of information.
Axis:

• I clinical disorders
• II Developmental disorders and personality disorders
• III General medical conditions
• IV Psychological and environmental problems
• V global assessment of functioning scale

Removal oaf the multiaxial system

The multiaxinal system developed for DSM-IV-TR is removed in DSM-5.
In place of the first three axes clinicians are simply to note psychiatric and medical diagnoses.

Organizing diagnoses by causes

DSM-5 defines diagnoses entirely on the basis of symptoms.

• Some have argued that advances in our understanding of etiology (causes) could help us rethink this approach.
  But our knowledge base is not yet strong enough to organize diagnoses around etiology.

In the DSM-5, the chapters are reorganized to reflect patterns of comorbidity and shared etiology.

Enhanced sensitivity to the developmental nature of psychopathology

Childhood diagnoses have been moved into other relevant chapters of DSM-5, to highlight the continuity between childhood and adulthood in forms of disorder.
Across diagnoses, more detail is provided about the expression of symptoms in younger populations.

New diagnoses

Several new diagnoses are proposed in the DSM-5.

Combining diagnoses

Some of the DSM-IV-TR diagnoses have been combined because there is not enough evidence for differential etiology, course, or treatment to justify labeling the conditions separately.

Clearer criteria

For many disorders, criteria have been rewritten to provide clearer guidance about thresholds for diagnoses.

Ethnic and cultural considerations in diagnoses

Mental illness is universal.
But there are many different cultural influences on the risk factors of mental illness, the types of symptoms experienced, the willingness to seek help, and the treatments available.

Rates of mental illness tend to be higher in the US than in many other countries.
To facilitate international communication, the DSM0-5 includes a list that cross-references the DSM diagnoses with the International Classification of Diseases and Related Health Problems (ICD) diagnoses.

DSM-IV-TR enhanced cultural sensitivity in three ways:

• By providing a general framework for evaluating the role of culture and ethnicity
• By describing cultural factors and ethnicity for each disorder
• By listing culture-bound syndromes in an appendix.

In DSM-5, culture-bound syndromes have been relabeled as cultural concepts of distress.
DSM-5 also includes a cultural formulation interview. The interview consists of 16 questions the clinicians could use to help understand how culture may be shaping the clinical presentation.

In the general framework, clinicians are cautioned not do diagnose symptoms unless they are atypical and problematic within a person’s culture.
Clinicians are advised to be constantly mindful of how culture and ethnicity influence diagnosis and treatment.

Attention is paid to how culture can shape the symptoms and expression of a given disorder.
In evaluating symptoms, clinicians also need to be aware that cultures may shape the language used to describe distress.

The DSM-5 includes 9 cultural concepts of distress in the appendix to describe diagnoses that are likely to be seen within specific regions.

Specific criticisms of the DSM

Too many diagnoses

• One side effect of the huge number of diagnostic categories is comorbidity.
  Comorbidity: the presence of a second diagnoses. The norm rather than exception.
• Many risk factors seem to trigger more than one disorder

Categorical classification versus dimensional classification

The DSM-IV-TR clinical diagnosis are based on categorical classification.
Does the patient have X or not?
Forces clinicians to define one threshold as ‘diagnosable’.
There is often little research support for the threshold defined.
Categorical diagnosis foster the false impression of discontinuity.

Dimensional system describe the degree of an entity that is present.

• They define a threshold for treatment

The DSM-5 preserves a categorical approach to diagnoses.
A dimensional approach to personality traits have been included in the appendix, but other diagnoses are based on categorical classification.

Reliability of the DSM in everyday practice

The increases explicitness of the DSM criteria has improved reliability.
But, because clinicians might not rely on the criteria precisely, the reliability of the DSM in everyday usage may be lower than that seen in research studies. Even when following criteria, there is some room for disagreement in DSM-5.

How valid are diagnostic categories?

The DSM diagnoses are based on pattern of symptoms.
One way of thinking about diagnoses is to ask whether the system helps organize different observations.
The central question is whether diagnoses made with the DSM criteria reveal anything useful about patients.

General criticisms of diagnosing mental illness

Diagnoses can have negative effects on a person.

• Diagnoses might contribute to stigma.
  But sometimes labels may actually relieve stigma by providing an explanation for the symptomatic behavior.
• When a diagnostic category is applied, we may lose sight of the uniqueness of that person.

Psychological assessment

There is no best assessment measure.
Using multiple techniques and multiple sources of information will provide the best assessment.

Clinical interviews

• Formal and structured
• Informal and less structured

Characteristics of clinical interviews

The attention the interviewer pays to how the responded answers questions, or does not answer them.

Great skill is necessary to carry out good clinical interviews.
The interviewer must obtain the trust of the person.

• Most clinicians empathize with their clients in an effort to draw them out and to encourage them to elaborate on their concerns.

Interviews may vary to the degree to which they are structured.

• In practice, most clinicians probably operate from only the vaguest outlines.
  Exactly how information is collected is left largely up to the particular interviewer and depends on the responsiveness and responses of the interviewee.
• To the extent that an interview is unstructured, the interviewer must rely on intuition and general experience.
• Reliability for unstructured clinical interviews is probably lower than for structured interviews.

Structured interviews

Structured interview: the questions are set out in a prescribed fashion for the interviewer.

Branching interview: the client’s response to one question determines the next question that is asked.
It also contains detailed instructions to the interviewer concerning when and how to probe in detail and when to go on to questions about another diagnosis.

In practice, most clinicians review the DSM symptoms in an informal manner without using a structured interview.

Assessment of stress

Measuring stress is important in the total assessment picture.
To understand the role of stress, we must first be able to define and measure it.
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 Bedfort college life events and difficulties schedule

Widely used to study life stressors.
The LEDS included and interview that covers over 200 different kinds of stressors. It is semistructured.
The interviewer and interviewee work collaboratively to produce a calendar of each of the major events within a given time period.
After the interview, raters evaluate the severity and several other dimensions of each stressor.

Goals

• Address a number of problems in life stress assessment.
• Exclude life events that might just be consequences of symptoms.

The LEDS includes a set of strategies to carefully date when a life stressor occurred.

Self-report stress checklists

Because intensive interview measures are so comprehensive, they take a good deal of time to administer.
Often clinicians and researchers want a quicker way to assess stress and may turn to self-report checklists.
These checklists typically list different life events and participants are asked to indicate whether or not these events happened to them in a specified period of time.
Difficulty:

• Great deal of variability in how people view these events
• Difficulties with recall

Personality tests

Self-report personality inventories

In a personality inventory, the person is asked to complete a self-report questionnaire indicating whether statements assessing habitual tendencies apply to him or her.
Standardization: the responses of a particular person can be compared with the statistical norms.

Minnesota multiphasic personality inventory (MMPI)
Designed to detect a number of psychological problems.
The MMPI has been widely used to screen large groups of people whom clinical interviews are not feasible.

In developing tests, the investigators used several steps

• Many clinicians provided statements that they considered indicative of various mental problems
• Patients diagnosed with particular disorders and people with no diagnoses were asked to rate whether hundreds of statements described to them.
• Items where selected for the final version of the test if patients in one clinical group responded to them more often in a certain way than did those in other groups.

With additional refinements, sets of these items were established as scales for determining whether a respondent should be diagnosed in a particular way.

Like many other personality inventories, the MMIP-2 is typically administered and scored by computer.
The MMPI-2 includes several ‘validity scales’ designed to detect deliberately faked responses.

Projective personality tests

A projective test: a psychological assessment tool in which a set of standard stimuli ambiguous enough to allow variation in responses is presented to a person.
The assumption is that because the stimulus materials are unstructured and ambiguous, the person’s responses will be determined primarily by unconscious processes and will reveal his or her true attributes, motivations, and modes of behavior. → The projective hypotheses.

The Thematic apperception test (TAT) is a projective test.
A person is shown a series of black-and-white pictures one-by-one and asked to tell a story related to each.
There are few reliable scoring methods for this test, and the norms are based on small and limited sample.
The construct validity of the TAT is also limited.

The Rorschach inktbolt test
Aperson is shown 10 inkblots, one a time, and asked to tell what the bold looks like.
Half the inkbolts are in black, white, and shades of gray, two also have red splotches, and three are in pastel colors.
Exner designed the most commonly used system for scoring the Rorschach test.

• Concentrates on the perceptual and cognitive patterns in a person’s responses.
• The person’s responses are viewed as a sample of how he or she perceptually and cognitively organized real-life situations.

The Exner scoring system has norms, although the sample on which they are based was rather small and did not represent different ethnicities and cultures well.
It is unclear whether the Rorschach provides information that could not be obtained more simply.

Intelligence tests

An intelligence test (or IQ test) is a way of assessing a person’s current mental ability.
Beyond predicting school performance, intelligence tests are also used in other ways:

• In conjunction with achievement tests, to diagnose learning disorders and to identify areas of strengths and weakness for academic planning.
• To help determine whether a person has intellectual developmental disorder
• To identify intellectually gifted children so that appropriate instruction can be provided them in school
• As a part of neuropsychological evaluations.

IQ is correlated with mental health.

IQ measures only what psychologists consider intelligence.

Behavioral and cognitive assessment

• Aspects of the environment that might contribute to symptoms
• Characteristics of the person
• The frequency and form of problematic behaviors.
• Consequences of problem behaviors

Direct observation of behavior

Cognitive behavior therapist try to fit events into a framework consistent with their points of view.
In formal behavior observation, the observer divides the sequence of behavior into various parts that make sense within a learning framework, including such things as the antecedents and consequences of particular behaviors.
Behavioral observation is also often linked to intervention. The cognitive behavioral clinician’s way of conceptualizing a situation typically implies a way to try to change it.

Many therapist contrive artificial situations in their consulting rooms or in a laboratory so they can observe how a client or a family acts under certain conditions.
Behavioral assessment

Self-observation

Self-monitoring: asking people to observe and track their own behavior and responses.

Ecological momentary assessment (EMA).
Involves the collection of data in real time as opposed to the more usual methods of having people reflect back over some time period.
Methods for EMA range from having people complete diaries at specified times during the day, to supplying them with smart-phones that do not only signal when reports are to be made, but also allow them to enter their responses directly into the device.

But
Behavior may be altered by the very fact that is is being self-monitored.
Reactivity: the phenomenon wherein behavior changes because it is being observed.

Cognitive-style questionnaires

Cognitive questionnaires tend to be used to help plan targets for treatment as well as to determine whether clinical interventions are helping to change overly negative thought patterns.

Dysfunctional attitude scale (DAS)

Neurobiological assessment

Brain imaging: ‘seeing’ the brain

• CT or CAT scan
• Magnetic resonance imaging MRI
• Functional MRI
• Position emission tomography (PET)

Neurotransmitter assessment

Metabolite: produced when a neurotransmitter is deactivated
A high level of a particular metabolite presumably indicated a high level of a neurotransmitter

• (Measuring from urine) do not direct refections of levels of neurotransmitter in the brain
• Correlational

To provide more experimental data, one strategy is to administer drugs that increase or decrease levels of neurotransmitters.

• Ethical?
• Drugs that change levels of one neurotransmitter often tend to influence other neurotransmitter systems.

Neuropsychological assessment

Neurologist: a physician who specialized in diseases or problems that affect the nervous system.
Neuopsychologists: a psychologists who studies how dysfunctions of the brain affect the way we think, feel, and behave.

Neuropsychological test are often used in conjunction with the brain imaging techniques just described. Both to detect brain dysfunction and to help pinpoint specific areas of behavior that are impacted by problems in the brain.

• Tactile performance test-time.
  While blindfolded, the patient tries to fit variously shaped blocks into spaces of a form board, first using the preferred hand, then the other, and finally both.
• Tactile performance test-memory
  After completing the timed test, the participant is asked to draw the form board from memory, showing the blocks in their proper location. Both this and the timed test are sensitive to damage in the right partietal lobe.
• Speech sound perception test
  Participants listen to a series of nonsense words, each comprising of two consonants with a long-e sound in the middle. They then select the ‘word’ they heard from a set of alternatives. This test measures left-hemisphere function, especially temporal and parietal areas.

Psychophysiological assessment

Psychophysiology: concerned with the bodily changes that are associated with psychological events.
Assessment are not sensitive enough to be used for diagnosis. But they can provide important information about a person’s reactivity and can be used to compare individuals.

The activities of the autonomic nervous system are often assessed by electrical and chemical measures to understand aspects of emotions.

• Heart rate
  Each heartbeat generates electrical changes, which can be recorded by electrodes placed on the chest that convey signals to an electrocardiograph.
  The signal is graphically depicted in an electrocardiogram (EKG), which may be seen as waves on a computer screen or on a roll of graph paper.
• Electrodermal responding of skin conductance.
• EEG

A cautionary note about neurobiological assessment

• Many of the measurements do not differentiate clearly among emotional states.
• Brain-imaging techniques do not allow us to manipulate brain activity and then measure a change in behavior.
• There is no one-to-one relationship between a score on a give neuropsychological test on the one hand and psychological dysfunction on the other.
• In attempting to understand the neurocognitive consequences of any brain dysfunction, one must understand the preexisting abilities that the patient had prior to diagnosis with a mental disorder.

Cultural and ethnic diversity and assessment

There are typically more differences within cultural, ethnic, and racial groups than there are between them.

Cultural bias in assessment

Cultural bias in assessment: a measure developed for one culture or ethnic group may not be equally reliably and valid with a different cultural or ethnic group.

Several steps in the translation process, including working with multiple translators, back-translating, and testing with multiple native speakers, can help to ensure that the test is similar in different languages.

Cultural factors may affect assessment in various ways

• Language differences
• Differing religions and spiritual beliefs
• The alienation or timidity of members of ethnic groups when being assessed by clinicians of the European American culture.

Strategies for avoiding cultural bias assessment

• Graduate training programs
  • Students must learn about basic issues in assessment
  • Students must become informed about the specific ways in which culture or ethnicity may impact assessment rather than relying on more global stereotypes about a particular cultural or ethnic group.
  • Students must consider that culture or ethnicity may not impact assessment in every individual case.
• Assessment procedures can be modified to ensure that the person truly understands the requirements of the task
• When the examiner and client have different ethnic backgrounds, the examiner may need to make an extra effort to establish a rapport that will result in the person’s best performance.