International Congress of the Royal College of Psychiatrists July 2012 Dr Alan Moss Consultant Neuropsychologist

Transcription

1 Role of effort testing and TOMM International Congress of the Royal College of Psychiatrists July 2012 Dr Alan Moss Consultant Neuropsychologist

2 POINTS TO BE COVERED Reliability of self report Test of Memory Malingering (TOMM) Consequences of failing TOMM on ability measures Reasons given for failure

3 The study of malingering has, we fear, been somewhat neglected by the scientific physician, who, more bent on establishing the features of true disease, has instinctively recoiled from the study of feigned disorders Jones and Llewellyn 1918 (Malingering, or the simulation of disease. Philadelphia:Blakiston s)

4 Are self reports accurate? What criteria do you use to determine if self report is accurate? What research is there to support your criteria?

5 Problems with self report Is it accurate? What is the origin of the symptom? Many symptoms are non-specific e.g. headaches, forgetfulness Many symptoms are common in the general population

6 THE GOOD OLD DAYS 90 referrals to a concussion clinic All were considered disabled from an MTBI and they were receiving financial compensation through the Worker s Compensation system. Patients provided post-injury and pre-injury retrospective ratings on the 16-item British Columbia Post-concussion Symptom Inventory (BC- PSI).

7 THE GOOD OLD DAYS Ratings were compared to 177 healthy controls recruited from the community and a local university. MTBI patients retrospectively endorsed the presence of fewer preinjury symptoms compared to the control group.

8 THE GOOD OLD DAYS Individuals who failed effort testing tended to retrospectively report fewer symptoms pre-injury compared to those patients who passed effort testing. Many MTBI patients report their preinjury functioning as better than the average person.

9 Test Of Malingered Memory TOMM Show 50 target pictures Choose which seen before from 50 pairs (correct errors) Show 50 same target pictures Choose which seen before from 50 pairs (new distracters, correct errors) 20 minute delay Choose which seen before from 50 pairs (new distracters)

10 Test Of Malingered Memory TOMM Therefore, on the third trial the target item will have been seen five times and the distracter item will be novel

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12 TOMM

13 Simply by guessing a score of approximately 25/50 would be expected Even those with confirmed severe head injury score >45 on second trial (mean 49.4) When TBI cases were instructed to fake bad they scored <45 (mean 32.1) Only dementia group scored near chance Lowest score 32/50 (mean 45.7)

14 Test Of Malingered Memory (TOMM) Lowest score in legal case 2/50 Lowest score in NHS case 12/50 This person had sustained a mild head injury (PTA <5 minutes). In litigation. She was complaining of severe whiplash symptoms and poor memory.

15 Lowest score in non litigating NHS cases 39/50 (MEAN 48/50) This lady was obviously grossly impaired (probable Alzheimer s disease) Reported that her memory was just like anybody else my age. Husband reported severe memory problems, confusion and wandering.

16 TOMM CLINICAL GROUPS Severe Traumatic Brain Injury (non-litigating) T1 T2 RET

17 50 TOMM CLINICAL GROUPS Dementia T1 T2 RET

18 TOMM CLINICAL GROUPS Depression (26 psychiatric inpatients, 4 having ECT) T1 T2 RET Rees et al 2001

19 TOMM CLINICAL GROUPS Psychotic In Patients T1 T2 RET Duncan et al 2005

20 TOMM CLINICAL GROUPS Mixed Psychiatric In Patients T1 T2 RET Gierok et. Al. 2005

21 TOMM CLINICAL GROUPS Induced Pain T1 T2 RET Etherton et. al. 2005

22 Motivation to Appear Impaired Forensic psychiatric in Patients T1 T2 RET Gierok et. Al. 2005

23 Motivation to Appear Impaired Pain (simulated poor memory) T1 T2 RET Etherton et. Al. 2005

24 Motivation to Appear Impaired TBI (instructed to fake) T1 T2 RET Tombaugh et. al 1996

25 UK DATA

26 Sample All litigating TOMM N= 468 Age 36.4 (16-72) Gender (m/f%) 70/30

27 PTA SEVERITY % PTA <5mins V mild PTA 5-60 mins Mild PTA 1-24 hours Moderate PTA 1-7 days Severe PTA 1-4 weeks Very severe PTA > 4 weeks Extremely severe 18.16

28 TOMM T2 by Severity Total sample 49 r =0.12 r 2 =0.013 p= Vertical bars denote 0.95 confidence intervals TOMM T SEVERIT Y

29 55 SEVERITY*TOMM passed/failed Vertical bars denote 0.95 confidence intervals TOMM T SEVERITY TOMM PASSED TOMM FAILED

30 Auditory Delayed by Severity TOMM Passers 105 Vertical bars denote 0.95 confidence intervals Auditory De SEVERIT Y

31 Auditory Delayed by Severity TOMM Failers 90 Vertical bars denote 0.95 confidence intervals Auditory Delayed SEVERIT Y

32 105 Vertical bars denote 0.95 confidence intervals Auditory Delayed SEVERITY TOMM passed TOMM failed

33 Visual Delayed by Severity TOMM Passers 100 Vertical bars denote 0.95 confidence intervals Visual Delayed SEVERIT Y

34 Visual Delayed by Severity TOMM Failers 90 Vertical bars denote 0.95 confidence intervals Visual Delayed SEVERIT Y

35 Visual Delayed passers and failers 100 Vertical bars denote 0.95 confidence intervals Visual Delayed SEVERIT Y TOMM Passed TOMM Failed

36 Full-scale IQ TOMM passers 110 Vertical bars denote 0.95 confidence intervals Full-Scale IQ SEVERIT Y

37 Full-scale IQ TOMM failers 100 Vertical bars denote 0.95 confidence intervals Full-Scale IQ SEVERIT Y

38 Full-scale IQ 110 Vertical bars denote 0.95 confidence intervals TOMM Passed TOMM Failed Full-Scale IQ SEVERIT Y

39 PIQ 105 TOMM Passed TOMM Failed Vertical bars denote 0.95 confidence intervals P IQ SEVERIT Y

40 V IQ 105 Vertical bars denote 0.95 confidence intervals TOMM Passed TOMM Failed V IQ: V IQ SEVERIT Y

41 What is the UK fail rate? % FAILING TOMM 40% 35% 30% 25% 20% 15% 10% 5% 0%

42 % With Abnormal Imaging (CT/MRI) PASSED FAILED

43 Glasgow Coma Scale PASSED FAILED 0

44 SCL-90 Anxiety PASSED FAILED

45 SCL-90 Depression PASSED FAILED

46 SCL-90 Hostility PASSED FAILED

47 SCL-90 GSI PASSED FAILED

48 % failing by referral source Claimant Defence Single joint

49 Excuses We should be grateful for an explanation as to how it comes that Dr. Moss signed a report when, as a matter of fact, (our client) has never met Dr. Moss I had a photograph of him in my consulting room and offered to submit test forms for fingerprint analysis

50 DM PTA HOURS HAD OPERATION DAY OF ACCIDENT 2 REPORTS FROM CLAIMANT NPs Latest one also treating him MINE NHS Neuropsychologist Claim for 24 hour care and would never work again

51 Failed 2 effort tests Inconsistent scores across assessments

52 Wife's statement after my assessment Dr Moss only interviewed my husband for 10 minutes

53 all of these deficits have had a profound affect and impact on his ability to engage in the assessment process. To me they are justification for the irrelevant responding that obviously occurred during X s assessment with Dr Moss. This confirms the opinion expressed in my report that Mr X was not fully cooperating with my assessment. It is simply not possible for me to produce a valid assessment of Mr X s difficulties if he was responding in an irrelevant manner.

54 during one of the tests, administered via computer, he said he just clicked on anything to get the whole of the tests over and done with. This. supports my contention that Mr X knowingly prevented me from obtaining an accurate and valid assessment of his difficulties.

55 WMT REACTION TIMES (seconds) PASS FAIL Mr X IR DR MC

56 RETESTED 2/12 LATER BY TREATING NEUROPSYCHOLOGIST EFFECT OF EFFORT ON WMT Warned Not Warned WMT IR WMT DR

57 REAL CASE Initially seen by neuropsychologist instructed by defence Failed 2 effort tests (very low scores) Concluded results not valid Claimant solicitor asked me to reassess Claimant told must do his best by his solicitor and myself

58 Passed the 2 effort tests given originally Passed 2 additional effort tests

59 EFFECT OF EFFORT ON WMS PTA 4 days Estimated pre morbid level Not Warned Auditory Immediate Visual Immediate Immediate Memory Auditory Delayed Visual Delayed Auditory Recognition Delayed General Memory

60 EFFECT OF EFFORT ON WMS Warned Not Warned Auditory Immediate Visual Immediate Immediate Memory Auditory Delayed Visual Delayed Auditory Recognition Delayed General Memory

61 CONCLUSIONS Self report cannot be relied upon Self reported problems do not equal pathology Any assessment must include an assessment of validity

62 CONCLUSIONS Test results from people who fail a symptom validity test cannot be regarded as a valid assessment of their true cognitive abilities Such results can only be taken to indicate the subject s minimum level of cognitive ability

63 Malingering? Why is malingering such a taboo word? Has major negative connotations Generally interpreted as meaning that there is nothing wrong with the claimant/patient. Will overshadow the fact that, in many cases, there will be real underlying difficulties

64 Surely not all effort test failures are innocent If it walks like a duck, quacks like a duck, looks like a duck, on the balance of probabilities. It just might be a duck Why are we so ready to suggest that it could be a dragon doing a duck impersonation.

65 Questions?