Why Test Effort?

In his Foreword to the manual for the Word Memory Test for Windows (Green, 2003), Dr. Paul Lees-Haley wrote “Neuropsychological assessments are no longer complete without evaluation of effort.”

In doing so, he was anticipating by at least two years the official position paper on Symptom Validity Testing from the National Academy of Neuropsychology (Bush, Ruff, Troster, Barth, Koffler, Pliskin, Reynolds and Silver, 2005, Archives of Clinical Neuropsychology, Volume 20, pages 419-426), which stated that it is necessary to evaluate symptom validity objectively in any neuropsychological assessment.

Similarly, in the first sentence of the abstract in a paper on ethics and the use of Symptom Validity Tests, Iverson states that effort tests are essential in neuropsychological assessments (Applied Neuropsychology, 2006, 13 (2), 77-90).  In fact, the first ethical failure listed by Iverson is failing to use well-researched and objective methods to identify invalid test scores (page 80, ethical consideration number 1).

Without satisfactory effort, not only neuropsychological test results but any ability test data gathered by psychologists or others are invalid. Poor effort on testing and exaggeration of cognitive complaints are commonplace, whether we are testing people with claims of cognitive deficits from any source, professional athletes pre- and post-concussion, university students seeking accommodations for ADHD or learning disabilities, prisoners facing sentencing, adults volunteering for normative studies or children in school. That is why it is important to have well-validated measures of effort.

In his review of the WMT (WMT Review) Dr. David Hartman described the work of Dr. Paul Green and his immediate colleagues as “the largest body of research on effort in the history of the profession” (2002, Archives of Clinical Neuropsychology, volume 17, pages 709-714). He indicated that future studies that do not objectively measure effort will soon be considered uninterpretable and unpublishable because effort explains so much variance in neuropsychological test scores. See the tables in this document showing just how big is the effect of effort on neuropsychological tests: Link:- The pervasive influence of effort on neuropsychological tests.

Dr. Green’s Word Memory Test (WMT) and his more recent, 5-minute verbal Medical Symptom Validity Test (MSVT) and the nonverbal equivalent (NV-MSVT) are computerized memory tests with multiple subtests measuring memory. They contain hidden measures, which serve to check the validity of the patient’s test scores. They go beyond the usual effort tests because they actually measure memory.  They each have norms from multiple different groups and they each produce profiles of scores across subtests of different levels of difficulty that are essential to interpretation.

These tests are unique because they allow us to differentiate between failure due to poor effort versus failure from very severe cognitive impairment, as in dementia. Simulators and dementia patients produce distinctly different profiles on WMT, MSVT and NV-MSVT. In fact, if someone has a dementia profile on all three tests, the likelihood that it is not dementia is extremely low. This follows from the fact that, in independent simulator studies in various countries, very few people asked to simulate impairment can produce a dementia profile on any one of these tests, let alone all three.

The WMT was invented by Dr. Paul Green as an oral test (Green and Astner, 1995) and then sold for a limited period on his behalf as a DOS computer program (Green, Allen and Astner, 1996). The WMT, MSVT and Non-Verbal-MSVT are now available to qualified professionals as MS Windows programs (Green, 2003) only by direct order from Green’s Publishing.

  • Green’s WMT for Windows offers computerized administration of the Word Memory Test.
  • Easy-to-use graphs and tables let you compare your client’s scores with those from any of 61 comparison groups (Total N is over 3,000 cases).
  • The MSVT program has even more comparison groups.
  • To inspect the WMT, MSVT or NV-MSVT programs just email Dr. Green and see for yourself or call Matt or John at +1 (236) 420-4351; Qualified professionals only: Please state profession, position and phone number).

Table 1:  Mean California Verbal Learning Test recall scores at each level of effort on WMT

N CVLT Short Delay Free Recall Mean CVLT SD Free SD CVLT
Long Delay Free Recall Mean
LD Free
91-100% 45 10.7 3.2 11.2 3.2
81-90% 206 8.3 3.2 8.9 3.2
71-80% 105 7.8 3.5 8.2 3.4
61-70% 61 7.4 3.0 7.3 3.3
51-60% 50 5.8 2.9 5.5 3.1
<=50% 34 4.4 2.5 3.3 3.0