lecture 3 Flashcards
two components of reliability and how is reliability measured?
Two components of reliability:
* Sensitivity - agreement regarding the presence of a particular
diagnosis
* Specificity - agreement concerning the absence of a particular
diagnosis
Reliability is measured by correlation (how closely two
variables are related)
subtypes of reliability
Inter-rater reliability
* refers to the degree to which two
independent observers or judges agree.
Test-retest reliability
* measures the extent to which people
being observed twice or taking the
same test twice score in generally the
same way.
* Only makes sense when the theory
assumes that people will not change
appreciably between testings on the
variable being measured.
Alternate-form reliability
* Uses two forms of a test.
Internal Consistency Reliability
* Assesses if the items on a test are
related to one another
types of validity
-content validity
- construct validity
- criterion validity
- case validity
content validity vs construct validity
Content validity
* refers to whether a measure adequately samples the
domain of interest.
Construct validity
* is a test or measure of some
characteristic or construct that
is not simply defined
(Cronbach & Meehl, 1955).
* is evaluated by looking at a
wide variety of data from
multiple sources.
* considers how well does the
diagnosis relate to other
aspects of the disorder.
criterion validity
Criterion validity
* is evaluated by determining whether a measure is
associated in an expected way with some other measure
(the criterion).
* concurrent validity (same point in time)
* predictive validity (a point in the future)
case validity
Case validity
* The focus is on validity of the interpretations and decisions
made with respect to a particular person.
* Case validity would be demonstrated when the person is
accurately assessed in their life context in a way that takes
into account interactions between the person and situations
as well as interactions of the person’s schemas.
* Case validity requires considering the person in typical
situations versus maximal situations (i.e., the difference
between how a person usually is versus what they are
capable of in atypical or extreme situations).
types of psychological assessments
- clinical interviews
- psychological tests
- behavioural and cognitive assessment techniques
clinical interview unstructured
- onset/course
- severity
- stressor
clinical interview structured
-SCID
-DSM diagnosis
- uses branching
- symptoms are rated on a three point scale of severity,
standardization/test norms
Standardization
* Responses of person being assessed are compared to test
norms that have been established.
Test norms
* The test is administered to many people and the responses
are analyzed to establish how a group of people tend to
respond.
* Provides a comparison context which is used to interpret an
individual’s score
personality inventories
The person is asked to complete a self-report
questionnaire indicating whether statements
assessing habitual tendencies apply to him or her
A cardinal feature of major depression is
anhedonia
what behavioural task is used to assess anhedonia
Probabilistic reward task
projective personality tests
a psychological assessment device in which a set
of standard stimuli, ambiguous enough to allow
variation in responses, is presented to the
individual
the projective hypothesis
As the stimulus materials are unstructured,
the client’s responses will be determined
primarily by unconscious processes and will
reveal his or her true attitudes, motivations,
and modes of behaviour.
how are intelligence tests used?
- To predict how well a child will perform in school
- To diagnose learning disabilities and to identify areas of
strengths and weaknesses for academic planning - To help determine whether a person has Intellectual
Disability - To identify intellectually gifted children
- In neuropsychological evaluations
emotional intelligence
Reflected in such abilities as delaying gratification and being sensitive
to the needs of others
types of brain imaging
-CT
-MRI
-fMRI
-PET
neuropsychological assessment
- To measure as reliably, validly, and completely as possible the
behavioural correlates of brain functions - To identify the characteristic profile associated with a
neurobehavioural syndrome (differential diagnosis) - To establish possible localization, lateralization, and etiology of a
brain lesion - To determine whether neuropsychological deficits are present
(i.e., cognitive, perceptual, or motor) regardless of diagnosis - To describe neuropsychological strengths, weaknesses, and
strategy of problem solving - To provide treatment recommendations (i.e., to client, family,
school)
The D2 test of visual attention
- The D2 Test of attention is used to assess the client’s
ability to sustain focused attention, engage in selection,
and visual scanning speed
testing for Dementia (cognition)
- Name and Address for Subsequent Recall Test
- Time orientation (what’s the date)
- Clock drawing
- information (what happened in the news recently)
- recall
psychophysiological assessment
Concerned with the bodily changes that accompany
psychological events or that are associated with a person’s
psychological characteristics
dimensional classification for diagnosis
- based on the premise that behaviour does not exist in
categories, but rather along dimensions - Mental disorders are examples of normal traits amplified to an
extreme
categorical classification for diagnosis
- i.e. the DSM
- The DSM is a categorical classification that divides mental
disorders into types based on criteria sets with defining features - A categorical system works best when:
- all members of a diagnostic class are homogeneous,
- when there are clear boundaries between classes,
- and when the different classes are mutually exclusive
- None of which apply to the DSM
The DSM5 system
The DSM is a system for diagnosing and
classifying individuals who are exhibiting
abnormal behaviours (thoughts, emotions)
diagnostic terms and specifiers
Presenting Problem: the reason for the visit
Principle Diagnosis: based on the presenting problem
Severity Specifiers: indicate the level of disability or impairment,
rating the intensity, frequency, duration, symptom count
Course Specifiers: indicate the progression of the illness
The old DSM system
the Earlier DSM (the fourth
edition) was a multi-axial
classification system
- Five “axes” – each person is rated
on five distinct dimensions (axes),
each of which refers to a different
domain in the person’s
functioning
DSM-5 elaborated four specific themes to be considered in
making cultural formulation:
- Cultural identity
- Cultural consideration of distress
- Cultural features of vulnerability and resilience
- Cultural features of the relationship between clinician and patient
criticisms of diagnosis
- Diagnosis is not explanation – diagnosing or labelling a person
as “suffering from depression” – does not explain the
underlying causes (but we often think it does) - A diagnosis can reduce the person to an illness (mental health
workers and/or society may just perceive the illness, and no
longer see the person)
rosenhan
Eight “pseudopatients” (three psychologists, a
pediatrician, a psychiatrist, a painter, and a housewife)
– all clinically sane
- Gained secret admission to 12 different hospitals
- Once admitted – the pseudopatients acted normally
and reported no symptoms - Each was released with a diagnosis of “schizophrenia in
remission” – none were classified as “sane”
Testability and Replicability in research methods
- A hypothesis must be amenable to systematic testing that
could show it to be false - What is observed must be replicable
- it must occur under prescribed circumstances not once, but
repeatedly
the role of theory
- Primary goal of science is to advance theories to account
for data, often by proposing cause–effect relationships.
operationism
- Each concept takes as its meaning a single observable
and measurable operation. - Each theoretical concept would be nothing more than
one particular measurable event. - However - if each theoretical concept is operationalized
in only one way, its generality is lost.
how is qualitative research and case study research similar?
- Qualitative research is similar to case study
research in that the focus is on the unique and rich
experiences of a small group of people who are studied in depth.
epidemiological research Focuses on determining three features of a disorder:
- Prevalence: Proportion of a population that has the disorder at a
given point or period of time - Incidence: The number of new cases of the disorder that occur in
some period, usually a year - Risk factors: Conditions or variables that, if present, increases the
likelihood of developing the disorder - Knowledge about risk factors can give clues to the causes of disorders
correlational method
- Measuring Correlation
- Correlation coefficient (r)
- May take any value between
+1.00 and -1.00 - Measures magnitude and
direction of relationship - Statistical Significance
- Likelihood results of an
investigation are due to chance - Often set in psychology at p =
.05
Applications of Correlational Methods to
Psychopathology
- Whenever we compare people given one diagnosis
with those given another or with people without a
psychological diagnosis, the study is correlational.
limitations of correlational methods
- Problems of Causality
- Critical drawback of correlational research
- Directionality problem
- Third-variable problem
developmental trajectory model
Collecting multiple observations of a particular behaviour
over time (longitudinal)
Group-based trajectory modelling
is based on evidence that it is impossible to distinguish clear
subgroups of participants in a sample even though it really is
important to distinguish these groups because:
- need to consider differing developmental factors
- best treatment options for people in subgroups
experimental methods
Gold standard for determining causality
Basic Features of Experimental Study Methods
- Researcher typically begins with an experimental hypothesis
- Investigator chooses an independent variable (IV) that can be manipulated
(different conditions – often experimental vs. control) - Participants are assigned to the conditions by random assignment
- Researcher arranges for the measurement of a dependent variable (DV)
- Analyze the data to determine if there has been an experimental
Single-Subject Experimental Designs
Participants are studied one at a time and experience a manipulated variable such
as a specific therapeutic treatment (there is no control group)
Mixed Designs
- The combination of experimental and correlational designs
- Classificatory or correlational variables (e.g., having
PTSD or not) are not manipulated nor created by the researcher - Experiments demand the manipulation of a variable (e.g., three types of treatment for major depression)
Meta-Analysis
- Used in psychotherapy research
- Involves the review of many studies in order to determine the effects of treatment
- Interesting because it is a way to examining published and unpublished studies, and combining the results
into a common format and then determining the extent of improvement, using a statistic called effect size
