Consideration of symptom validity as a routine component of forensic assessment, Erin Eggleston
1. Consideration of Symptom Validity
as a Routine Component of
Forensic Assessment
Erin Eggleston PhD DipClinPsych
Reg. Clinical Psychologist
2. What I mean by Symptom
Validity….
The measurement or observation of
bias in test behaviour and self
reported psychopathology.
response bias
motivational inhibition / test underperformance
dissimulation / intentional feigning
self debasement
self enhancement / denial of everyday life
complaints/ presenting overly favourably
symptom exaggeration / magnification
symptom under reporting
3. What I mean by the forensic…
Expert provision of clinical evidence
to inform decision making or court
proceedings.
In New Zealand psychologists have
long been used as experts in the
Family Court.
This type of assessment role is
growing as what we can do becomes
better understood.
4. Pitfalls when psychology interfaces
with law…
“If I talk with you, you’ll find out things about
me and then the Parole Board will find out
and keep me in longer” (offender, abridged)
“You Psychologists just say I’m high risk – that
doesn’t help me. So no I don’t consent”
(offender, abridged)
5. Making the Case….
for knowing about and being able to
deliver basic Symptom Validity tests
as part of clinical screen in forensic
settings.
For being willing to test the validity
and robustness of our psychological
findings
Regarding the risks of not being
sure about symptom validity.
6. Incidence
The known base rate internationally for
symptom exaggeration in neuropsychological
field ranges from 7.5% to 33% in clinical
settings.
30-40% in settings where incentive exists…..e.g
compensation, classification and parole..but to
be fair we don’t know in NZ.
Not sure of the numbers in the opposite
direction where incentive exists..e.g denial,
symptom minimisation.
Donders and Boonstra, 2007, Green, Rohling, Lees-Haley & Allen 2001; Binder and
Rohling, 1996; Lees-Haley, 1992; Trueblood & Schmidt, 1993:
7. What does the psych board say?
The psychologist should be alert to motivational factors
which may bias the results in a particular direction. Do
we consider these factors?
Where there is reason to question effort, symptom
validity assessment may be included… Hmm
Be careful…they are worried about us talking about
Malingering… Do we?
While psychologists often want to avoid having this
uncomfortable discussion, there is an obligation to
feedback the results of the assessment to the client.
Do we agree?
Draft Guidelines on Use of Psychometric Tests NZ
Psychologist Board (Dec 2011)
8. Psychometric review – tests examine:
Psychiatric Symptoms (Rare, Improbable Absurd combinations, Severity,
Consistency, and Report Versus Observed).
Self Deception
Validity Scales on Personality Tests
Memory symptoms
IQ (VIP)
Substance Abuse
Somatic Perception
Embedded measures across test batteries
Best practice suggests converging test data.
10. Case One: s38 Sexual Offender
Psychiatrist says fit to plead and no
evidence of intellectual impairment
Lawyer says clear ID.
Only a psychologist can sort this out
11. Testing
Passed TOMM x2
FSIQ in range of <60 (no difference across subtests)
Very good at saying yes.
BURT 6.5 year reading age
Vineland II across two raters consistent with ID
Special schooling, no employment, limited coping skills
It was the symptom validity test that
stood out strongly in court to show
this was a valid assessment of
functioning.
12. Case Two: ACC Data Assessment
(Risky/ SV testing recommended)
PAI: strong negative bias
DAPS: strong negative bias
VIP / TOMM: valid.
MSPQ: four times above cut-off for
back pain
K10: severe
CES-D: v.severe in range where
inpatient care should be considered.
13. Where we got to with some feedback…
Some rapport was established by meeting
twice.
Client agreed with strong negative bias
Client agreed with paranoid ideation and
pervasive distrust, aggrieved, suspected that
others plotting against him. This was the
substantive barrier to change.
Noted incentives
Does meet criteria for PTSD but is difficult to
treat.
Warrants specialist treatment (Psychiatry,
Clin.Psychology)
14. Case Three: s333 Youth court
Youth considered by Social Worker
based on previous psychology
report to have ID and would likely
be placed in Youth ID Service
Wanting to know what it would
mean if he scored lower vs. higher
Knows that offending is serious and
persistent enough to lead to district
court sentencing.
15. Prior test results…
WAIS IV (previous psych)
Scores spanned from the extremely low range – scaled
score of 1 to the average range - scaled score of 10.
Matrix reasoning- which is a robust indicator of overall
intelligence that is not impacted by schooling was in the
average range;
Client admitted to engaging in previous tests with low
effort and that he was considering doing so with me
because he considered being found to be low
functioning would be useful in his court (incentive);
16. Case Four: [ACC] PTSD as a
consequence of physical injury
Referral: Assessment of the likely pre-injury mental health
condition and any mental condition (using DSM-IV) that is
subsequent to this and can be reliably linked to the covered
physical injury. This should include close examination of
the possibility of Post Traumatic Stress Disorder any other
cognitive, behavioural or emotional patterns that might
explain reported findings.
17. Symptom Validity findings…
The pattern detected across psychometric tests, clinical
interview data and corroborative sources indicated that while
Ms Jones did not actively or intentionally feign illness or
falsify symptoms, self-report was unreliable and likely to
include exaggerated symptoms. Ms Jones’s approach to
cognitive testing was reported as inconsistent; that is, there
was evidence of periods of optimum and sub-optimum effort.
Structured Inventory of Reported Symptoms
Millon Clinical Multiaxial Inventory –III
Validity Indicator Profile
Behavioural Evidence
Personal Motivators
Observed Testing Behaviour
19. Practice points
Be a scientist practitioner and strengthen
psychological contribution to forensic environment by
openly testing alternative hypotheses and the validity
of our conclusions.
Learn from the forensic field: Assess patterns
across test data, note clinical and behavioural
observations, consider incentives and use a range of
corroborative sources.
Develop rapport and inform clients of the
components of the assessment
Describe and formulate on response style.
Develop this component of your forensic report.
Consider the utility of feedback and how best to
communicate your results both in terms of developing
your formulation and being fair to the client in terms of
hearing your findings first from you.
Editor's Notes
Capture all term.
Fitness to plead NZ Parole Board assessments of offending behaviour, risk, change and related issues s333 youth court Assessments of Mental Injury as a consequence of Physical injury or Criminal Act (ACC) Neuropsychological Assessment Eligibility for ID Compulsory Care and Rehab. As my GP medical advisor colleague who I sit next to at ACC says – you psychologists are taking over the world….
The power of the Psychologist as change agent may have has been eroded by us becoming involved in such decision making. Informed Consent. Clients may become suspicious of psychologists motives. Will we be considered as agents of the state?
See diagnosis of ID and institutionalisation.
Forced choice tests…TOMM Lower Sensitivity..test ability to ID actual postives is low High Specificity: proportion of negatives correctly iD. I.e few false positives True positive: Dissimulators correctly identified False positive: Healthy people incorrectly identified as dissimulators True negative: Healthy people correctly identified as healthy False negative: Dissimulators incorrectly identified as healthy.
The need for Symptom validity testing is an accepted standard and integral part of the neuropsychological assessment. What about other areas of practice as we have discussed..there are many that fall outside of neurpsychology. There is ample evidence that poor performance on SV tests undermines the confidence that can be placed in the results of Neuropsychological findings. For example… Failure on SVT invalidates the relationship between neuropsychological results and brain damage. (Fox, 2011, The Clinical Neuropsychologist). Sort of important..right?
SIRS: MCMI-III…known to correctly classify psychiatric inpatients and known to be only slightly better than chance at identifiying feigned psychopathology MCMI-III (PPP= positive predictive power, NPP=negative predictive power) Scale X raw scores > 178 failed to identify any of the student malingerers, resulting in a PPP of 0 but a hit rate of 63.1% because all of the psychiatric inpatients were correctly classified. Scale X BR score > 89 maximized the validity of decisions based on using a cutoff score to differentiate student malingerers from bona fide psychiatric inpatients. The maximum PPP achieved was 63.8% by Scale X, indicating that when a BR score of 89 was exceeded, the probability that the person was malingering was somewhat better than chance
TOMM is probably not best practice for ID…not sure what is. But I think in this case with an FSIQ of <60 , a good pass on the TOMM is impressive.
Psychologist made no particular error really..more so the communication of the results was not as clear as it could have been. EG. Using .. What this means is …. RESULTS…performance on the Stanford Binet 5 (SB5) was of overall intelligence in the average range for his age, with an IQ of 90-98 (95% confidence). There were no significant differences favouring verbal (language) or non-verbal intelligence. The profile is consistent was someone with a normal learning trajectory and a knowledge score that was impacted by low exposure to learning opportunities whether in or out of school. There was no evidence of cognitive deficit that would suggest a learning problem, brain injury or disability. - while it is possible to score worse than one’s potential, for various reasons, it is not possible to score better than ones actual ability I did have a forced choice symptom validity measures available but in the end did not need it.
Difference between test data and opinion in court is an interesting distinction. Psychology evidence can sometimes be the most robust because of our willingness to test alternative hypotheses.