Children's Ability to Malinger Cognitive Deficits

154 Pages·2017·3.9 MB·English

by  Jesse Elterman

Children’s Ability to Malinger Cognitive Deficits
by
Jesse Emil Elterman
M.A. (Psychology), Simon Fraser University, 2007
B.A. (Psychology), University of Victoria, 2005
Thesis Submitted in Partial Fulfillment of the
Requirements for the Degree of
Doctor of Philosophy
in the
Department of Psychology
Faculty of Arts and Social Sciences
 Jesse Emil Elterman 2018
SIMON FRASER UNIVERSITY
Spring 2018
Approval
Name: Jesse Emil Elterman
Degree: Doctor of Philosophy
Title: Children’s Ability to Malinger Cognitive Deficits
Examining Committee: Chair: John McDonald, Ph.D.
Professor
Deborah Connolly, LL.B., Ph.D
Senior Supervisor
Professor
Kevin Douglas, LL.B., Ph.D.
Supervisor
Professor
Allen Thornton, Ph.D., R.Psych.
Supervisor
Professor
Charlotte Waddell, MD, FRCPC
Internal Examiner
Professor
Faculty of Health Sciences
Jennifer Batchelor, Ph.D.
External Examiner
Director Clinical Neuropsychology
Department of Psychology
Macquarie University
Date Defended/Approved: January 24, 2018

ii
Ethics Statement

iii
Abstract
Historically, psychologists have not assessed performance validity in child assessments
where there is potential for secondary gain, although children’s ability to malinger is a
growing concern among psychologists. The present series of three simulation studies
examined (1) children’s ability to withhold their best effort on psychological testing, (2)
whether performance validity tests (PVTs) can accurately detect withholding, and (3)
whether inhibitory control explains individual differences in withholding. Participants were
children in grades four and six, and performance was measured using the WISC-IV PSI
subtests and the RAVLT. PVTs included the MSVT and TOMM. Children were instructed
to either try their best (BE condition) or withhold (WE condition) based on instructions in
a storybook read to children by their parent/guardian the night before the testing session.
Study 1 used a repeated measures design to first assess best effort and then children
were either given the BE or WE storybook. Both cohorts of children in the WE condition
performed worse on the RAVLT and PSI than children in the BE condition, the PVTs
obtained moderate accuracy, and inhibitory control was unrelated to withholding. Study 2
examined whether prior exposure to the testing materials was necessary for children to
withhold and only included one testing session. Children in grade 4 scored lower on the
PSI than their best effort comparison group, but otherwise scores on the performance
tests were not statistically different between groups based on instructions given. There
were significant differences between the groups on the MSVT, although the classification
accuracy was only moderate. Study 3 examined whether children could withhold their
best effort without being reminded of the instructions prior to the testing session. There
were no differences on the performance tests or PVTs between those instructed to
withhold and the best effort comparison group, although the variances on the MSVT
were unequal, suggesting that the instructions had an effect, albeit subtle. Overall, the
results show that fewer children can withhold their best effort as the task becomes more
difficult, but nevertheless some can still withhold under certain conditions. Limitations,
future directions, and implications for clinical practice are discussed.
Keywords: Child; Malingering; Cognitive Deficits.
iv
Acknowledgements
I would like to thank my senior supervisor, Dr. Connolly, for her support, encouragement,
and dedication throughout my graduate studies. I would also like to thank my committee
for their advice and lending their expertise in conducting this research.
This dissertation would not have been possible without the support of my family, friends,
and professional colleagues who had confidence in me and helped lift me up during the
challenges one faces when completing a dissertation. I am forever grateful to all of you.
v
Table of Contents
Approval .............................................................................................................................ii
Ethics Statement ............................................................................................................... iii
Abstract .............................................................................................................................iv
Acknowledgements ........................................................................................................... v
Table of Contents ..............................................................................................................vi
List of Tables ................................................................................................................... viii
Chapter 1. Children’s Ability to Malinger Cognitive Deficits ................................... 1
1.1. Malingering & Detection ........................................................................................... 2
1.2. Tort Law ................................................................................................................... 6
1.3. Detecting Deception ............................................................................................... 12
1.4. Development of Lying Ability in Children ................................................................ 26
1.5. Executive Functioning. ........................................................................................... 28
1.6. The Current Research Studies ............................................................................... 32
Chapter 2. Study 1 ..................................................................................................... 34
2.1. Method ................................................................................................................... 34
2.2. Results ................................................................................................................... 41
2.3. Discussion .............................................................................................................. 55
Chapter 3. Study 2 ..................................................................................................... 58
3.1. Method ................................................................................................................... 59
3.2. Results ................................................................................................................... 61
3.3. Discussion .............................................................................................................. 72
Chapter 4. Study 3 ..................................................................................................... 76
4.1. Method ................................................................................................................... 77
4.2. Results ................................................................................................................... 78
4.3. Discussion .............................................................................................................. 88
Chapter 5. General Discussion ................................................................................ 91
5.1. Children’s Ability to Withhold .................................................................................. 92
5.2. Relationship between Withholding and Inhibitory Control ...................................... 97
5.3. The Effectiveness of PVTs to Detect Withholding .................................................. 99
5.4. Relationship between Failing a PVT and Ability-Based Test Scores ................... 101
5.5. Limitations and Future Directions ......................................................................... 102
5.6. Implications for Clinical Practice ........................................................................... 105
vi
References ................................................................................................................ 107
Appendix A. Medical History Questionnaire .......................................................... 121
Appendix B. Script for Obtaining Assent and Debriefing Participants ................ 122
Appendix C. Counterbalanced Test Order.............................................................. 123
Appendix D. Storybooks ........................................................................................... 131

vii
List of Tables
Table 1. Mean (SD) scores for the RAVLT (Time 1 & 2), PSI (Time 1 &
t1-5
2), Information, Stroop, and NEPSY-Inhibition tests as a function
I
of grade and instruction given ................................................................. 42
Table 2. Number of instructions participants in the withholding condition
could recall after the second testing session expressed as
percentages separated by grade cohort .................................................. 43
Table 3. Unstandardized means and standard deviations for participants in
the withholding condition on the Stroop and NEPSY-Inhibition
I
tests as a function of grade ..................................................................... 45
Table 4. Mean (SD) change scores for participants in the withholding
condition as a function of DV and grade .................................................. 46
Table 5. Mean (SD) MSVT Scores Across Grade and Instruction Group ............. 48
Table 6. Correlations between subscales of the MSVT among participants
in the withholding condition as a function of grade .................................. 48
Table 7. Statistical tests for the effect of instructions on the MSVT
subscales ................................................................................................. 50
Table 8. Correlations between change scores on the PSI and RAVLT
t1-5
with scores on the MSVT among children in the withholding .................. 51
Table 9. Proportion of participants that were classified as true positives
(TP), true negatives (TN), false positives (FP), and false negatives
(FN) by the MSVT .................................................................................... 52
Table 10. Proportions of participants in each instruction group who obtained
negative RCI scores greater than one standard deviation on either
the PSI or RAVLT as a function of instruction given. ........................... 53
t1-5
Table 11. Comparison of Study 2 participants to comparison group ....................... 58
Table 12. Mean (SD) scores for the RAVLT and PSI for participants in the
t1-5
withholding and comparison groups as a function of grade and
instruction given ....................................................................................... 61
Table 13. Mean (SD) MSVT scores across grade for participants in the
withholding group and comparison group ................................................ 63
Table 14. Mean (SD) TOMM scores for participants in the withholding group
as a function of grade .............................................................................. 63
Table 15. Correlations between subscales of the MSVT among participants
in the withholding condition as a function of grade .................................. 64
Table 16. Comparison of MSVT subscale scores between instruction groups ....... 65
viii
Table 17. Proportion of participants that were classified as true positives
(TP), true negatives (TN), false positives (FP), and false negatives
(FN) by the MSVT .................................................................................... 66
Table 18. Proportion of participants in the withholding group that were
classified as true positives (TP) and false negatives (FN) by the
TOMM ...................................................................................................... 66
Table 19. Proportions of participants in each group who obtained scores
lower than one standard deviation below the mean on either the
PSI or RAVLT as a function of grade and instruction group. ............... 67
t1-5
Table 20. Proportion of participants that were classified by the MSVT as true
positives (TP), true negatives (TN), false positives (FP), and false
negatives (FN) as a function of obtaining scores on either or both
measures above or below the -1 SD cut-off. ........................................... 68
Table 21. Proportion of participants that were classified by the TOMM as
true positives (TP), true negatives (TN), false positives (FP), and
false negatives (FN) as a function of obtaining scores on either or
both measures above or below the -1 SD cut-off .................................... 68
Table 22. Mean (SD) scores among participants instructed to withhold their
best effort as a function of whether or not they passed both PVTs ......... 69
Table 23. Comparison of Study 3 participants to comparison group ....................... 76
Table 24. Mean (SD) scores for the RAVLT and PSI for participants in the
t1-5
withholding group and the comparison group as a function of
grade and instruction given ..................................................................... 79
Table 25. Mean (SD) MSVT scores across grade and instruction given for
participants in the withholding group and comparison group .................. 80
Table 26. Mean (SD) TOMM Scores for Participants in the Withholding
Group as a Function of Grade ................................................................. 81
Table 27. Correlations between subscales of the MSVT among participants
in the withholding condition as a function of grade .................................. 81
Table 28. Comparison of MSVT subscale scores between instruction groups ....... 82
Table 29. Proportion of participants that were classified as true positives
(TP), true negatives (TN), false positives (FP), and false negatives
(FN) by the MSVT .................................................................................... 83
Table 30. Proportion of participants in the withholding group that were
classified as true positives (TP) and false negatives (FN) by the
TOMM ...................................................................................................... 83
Table 31. Proportions of participants in each group who obtained scores
lower than one standard deviation below the mean on either the
PSI or RAVLT as a function of grade and instruction given ................. 84
t1-5
ix
Table 32. Proportion of participants that were classified by the MSVT as true
positives (TP), true negatives (TN), false positives (FP), and false
negatives (FN) as a function of obtaining scores on either or both
measures above or below the -1 SD cut-off ............................................ 85
Table 33. Proportion of participants that were classified by the TOMM as
true positives (TP), true negatives (TN), false positives (FP), and
false negatives (FN) as a function of obtaining scores on either or
both measures above or below the -1 SD cut-off .................................... 85
Table 34. Mean (SD) PSI and RAVLT scores for participants who passed
t1-5
both PVTs or were detected by at least one PVT .................................... 86
x