1. Pilot Study for a Novel Measure Designed to Detect ADHD Simulators
Feder, A., Courrégé, S., Boress, K., and Skeel, R.
Central Michigan University
Introduction
Marshall et al. (2016) showed that true ADHD groups and groups expending suspect effort or exaggerating symptoms are nearly indistinguishable in typical ADHD assessments, suggesting that more than 60% of individuals demonstrating suspect effort may be diagnosed with ADHD.
Individuals attempting to receive an ADHD diagnosis and associated secondary gains may not be distinguishable from true ADHD by the number of symptoms endorsed but may present with more severe symptoms (Marshall et al., 2016).
Traditional assessment tools designed to assess for suspect effort may not be sufficient to identify those exaggerating symptoms of ADHD, and may not be administered in evaluations without cognitive measures.
Objective
The present study evaluated a new self-report measure, the ADHD Symptom Infrequency Scale (ASIS), developed to identify individuals exaggerating symptoms in order to meet the criteria for Attention-Deficit/Hyperactivity Disorder (ADHD).
Results
As expected, controls endorsed significantly fewer ADHD symptoms than the true ADHD group on the BAARS-IV, t(52) = 7.16, p < .001, and the total ASIS, t(56) = 7.07, p < .001.
Items meant to detect symptom exaggeration were endorsed at a significantly higher rate for simulators compared to the other three groups, F(3, 102) =29.73, p < .001.
The optimal cut point resulted in a positive predictive value of 86% and a negative predictive value of 66%. Item level analysis revealed a subset of items that were particularly effective in discriminating between groups.
Table 1
Mean Comparisons
Group (N)
ASIS Total
Mean (SD)
ASIS Infrequency
BAARS-IV Total
Control
(N = 30)
33.7 (6.24)
66.8 (6.35)
28.9 (11.0)
ADHD
(N = 28)
44.0 (4.44)
78.3 (6.67)
48.8 (9.28)
“Think” ADHD
(N = 17)
44.9 (4.73)
80.0 (8.22)
46.4 (12.0)
Simulators
(N = 31)
47.8 (8.08)
86.4 (10.7)
57.9 (14.0)
F test
F(3,102) = 32.8,
p < .001
F(3, 102) = 29.7,
F(3, 97) = 29.3,
Note. Using analysis of variance test, we compared means for each group on the ASIS total scale score, ASIS infrequency item scale score, and the BAARS-IV total scale score. SD = standard deviation. Total N = 97 for the BAAR-IV mean comparisons, with one simulator and four controls not completing this measure completely.
Method
Participants:
140 participants were recruited online through Amazon Mechanical Turk.
After screening for eligibility and removing invalid profiles, 106 participants were retained (50% female, 75% Caucasian, age range = 18-58, mean age = 33, SD = 9.8).
Procedure:
A four group comparisons model (control, ADHD-diagnosed, an undiagnosed but self-reported possible ADHD, and analogue simulators) examined differences in endorsement rates across the ASIS.
Those in the ADHD-diagnosed group provided details about their ADHD assessment.
The ADHD and control groups were instructed to answer both questionnaires honestly.
The simulator group was instructed to complete the questionnaires as if trying to believably convince a doctor they had ADHD in order to receive medication. They were explicitly educated with examples of inattention, hyperactivity, and impulsivity.
Measures:
Barkley Adult ADHD Rating Scale – Fourth Edition (BAARS - IV) Self-Report Form
As a validity check participants completed the self-report form of current symptoms to assess current ADHD symptoms associated with DSM-5 diagnostic criteria. Items were rated on a four-point scale.
ADHD Symptom Infrequency Scale (ASIS)
Participants completed 83 true-false items assessing true ADHD symptoms and items designed to be endorsed at a higher rate by those exaggerating ADHD symptoms.
Example items include:
I avoid nice restaurants because meals take too long.
People seem to think I am a good listener.
Discussion
This study suggests that the ADHD Symptom Infrequency Scale has potential as a reliable and valid measure of ADHD, with the ADHD symptom portion of the scale performing similarly to an established measure of ADHD symptoms.
This measure is sensitive to malingering and exaggeration of symptoms, with the symptom exaggeration portion of the scale distinguishing successfully those in the control group, true ADHD group, and simulating ADHD group.
Specific subsets of items that were successful in distinguishing between simulators and true ADHD were developed and identified as unusual symptoms of ADHD and negative attributes about those with ADHD.
Further development of items that identify ADHD simulators and examination in additional samples is warranted.
Selected References
Marshall, P.S., Heyerdahl, D., Hoelzle, J.B., & Nelson, N.W. (2016). The impact of failing to identify suspect
effort in patients undergoing adult attention-deficit/hyperacticity disorder (ADHD) assessment.
Psychological Assessment, 28(10),
For more information - including references - please contact Reid L. Skeel at