Lecture 11: Application of Assessment in Clinical Settings Flashcards
What is the difference between assessment and testing?
Testing: a particular scale is administered to obtain a specific score and a
descriptive meaning can be applied to the score on the basis of normative,
nomothetic findings.
• Assessment: concerned with the clinician who takes a variety of test
scores, generally obtained from multiple test methods, and considers data in
the context of history, referral information, and observed behaviour to understand the person being evaluated, to answer the referral questions, and then to communicate findings to the patient, his or her significant
others and referral sources.
Why should we assess?
- describe current functioning
- confirm, refute, or modify impressions formed by clinicians
- identify therapeutic needs, highlight issues likely to arise in treatment, recommend forms of interventions and offer guidance about likely outcomes
- aid in differential diagnosis
- monitor treatment over time to evaluate the success of interventions
- manage risk (untoward treatment reactions, potential legal liabilities)
- provide skilled, empathic assessment feedback as a therapeutic
intervention in itself.
Why should we use standardised tests?
Clinicians are unreliable judges
Why are clinicians unreliable judges?
Errors in gathering data: -tendency to see patterns where none exist • tendency to seek confirmatory evidence • use of preconceived biases Errors in synthesising data • heuristics in clinical judgement (Tversky & Kahneman, 1974) • representativeness • availability • anchoring
Types of tests used by clinicians
-Diagnostic interviews • Self-report questionnaires • Questionnaires completed by significant others • Behavioural tests • Observational methods
What are diagnostic interviews?
Fully or semi structured
Ensure coverage of the diagnostic criteria as specified by DSM-5 (few errors in gathering data)
Rules for scoring the interview are specified (few errors in synthesing data)
e.g. 1 in 5 people etc etc
What is a reliability for structured diagnostic interview
Inter-rater agreement (two clinicians come up with same diagnosis)
-Test-retest reliability
What is a validity for structured diagnostic interview
- Validity of diagnostic criteria
- What is the “gold standard”? Is a LEAD standard better?
- Procedural validity
LEAD- expert who knows client, who has access to all data
What are the statistics used?
- Kappa coefficients
- Sensitivity (probability that a person will
What is Kappa?
A measure of agreement corrected by chance.
What is sensitivity?
• Probability that a person with a clinical diagnosis will
receive the same diagnostic interview diagnosis
What is specificity
Probability that a person without a clinical diagnosis will not receive that diagnosis via the diagnostic interview
What is Positive predictive values
Probability that a person with a diagnostic interview diagnosis is truly “ill”
What is negative predictive values?
Probability that a person without a diagnostic interview
diagnosis is truly “well”
What is the sensitivity equation?
a/a+c
What is specificity equation?
d/b+d
What is the PPV equation
a/a+b
What is NPV?
d/d+c
What is the equation for Kappa?
k= Po-Pe/ 1-Pe
What is Po?
Observed population
What is the equation for Po?
Po=(a+d)/n
What is Pe?
The proportion expected by chance?
What is the equation for Pe?
(a+b)(a+c)/n + (c+d)(b+d)/n
What are the interpretation scales?
≥ .75 - excellent agreement .6 to .74 – good agreement .4 to .59 – fair agreement less than .4 – poor agreement 0 – agreement at chance level
What is a global measure questionnaires?
Assess multiple symptoms
Provide an overall level of severity of psychopathology
What is specific measures questionnaires
Assess a limited set of symptoms
Provide measures of the level of severity of a specified problem.
What is the BSI?
Designed to reflect psychological symptom patterns of patients and non-patients.
53 items.
Items rated on 5 point scale
Adequate reliability and validity
What is the BAT
BEhavioural avoidance test
How do you judge whether the client is making appropriate progress or has had a good outcome as an outcome of treatment?
Statistical vs Clinical significance
What is statistical significance?
Group means are compared and if the difference between the means is found to occur beyond the range of chance (generally 0.05 p), the difference is significant.
HOWever, the difference may not be meaningful, small changes can be statistically significant, and not everyone in the group improves
What is clinical significance?
Individual level of analysis
Meaningful changes
What are the two criteria necessary for an individual to to have clinically significant change
Improvement: The dependent measure must show a reliable change that is larger than the measurement error of the instrument (reliable change index)
Recovery: After treatment, the individual’s score on the dependent measure is more likely to be drawn from the distribution of a functional than a dysfunctional population.
What is the equation for RCI?
RC=X2-X1/ Sdiff
X1 = individual’s pre-treatment score X2 = Individual’s postttreatment score Sdiff = standard error of the difference between the two scores
What are 3 ways to operationalise normal functioning? (part of recovery)
a. post-treatment score should fall outside the range of the dysfunctional
population, where range is 2 sd’s beyond the mean
b. post-treatment score should fall within the range of the functional
population (within 2 sd’s of the mean)
c. post-treatment score is closer to the mean of the functional than of the
dysfunctional population
