Symptom validity assessment: Practice issues and medical necessityNAN Policy & Planning Committee

Abstract

Symptom exaggeration or fabrication occurs in a sizeable minority of neuropsychological examinees, with greater prevalence in forensic contexts. Adequate assessment of response validity is essential in order to maximize confidence in the results of neurocognitive and personality measures and in the diagnoses and recommendations that are based on the results. Symptom validity assessment may include specific tests, indices, and observations. The manner in which symptom validity is assessed may vary depending on context but must include a thorough examination of cultural factors. Assessment of response validity, as a component of a medically necessary evaluation, is medically necessary. When determined by the neuropsychologist to be necessary for the assessment of response validity, administration of specific symptom validity tests are also medically necessary.

Neuropsychologists’ ability to predict distorted symptom presentation

“…Taken together, our results support the notion that it is important to routinely test for distorted symptom presentation (Bush et al, 2005;Heilbronner et al, 2009). Yet, our findings are silent about how clinicians will integrate response validity test scores in their diagnostic conclusions.…”

“…Major professional organizations in neuropsychology have issued policy statements that stress the routine use of SVTs and PVTs (National Academy of Neuropsychology, Bush et al, 2005 Heilbronner, Sweet, Morgan, Larrabee, & Millis, 2009). These developments reflect neuropsychologists' increased sensitivity to the diagnostic option of distorted symptom presentation and how it can be evaluated with specific tests.…”

Subjective cognitive complaints and neuropsychological test performance following military-related traumatic brain injury

“…First, we excluded participants from the final sample for poor cognitive effort based on a single symptom validity measure (i.e., WMT). While the WMT is considered to be a clinically valid and reliable measure, current clinical guidelines recommend using more than one symptom validity measure for the purposes of detecting poor cognitive effort [66][67]. It is possible that we included some people who had been misidentified as providing adequate effort when, in fact, they provided inadequate effort.…”

Avaliação da simulação ou esforço insuficiente com o Rey 15-Item Memory Test (15-IMT): Estudos de validação em grupos de adultos idosos

“…Por outro lado, são vários os autores que advertem para a necessidade de se conceptualizar os comportamentos de simulação num continuum (cf. por exemplo, Bush, Ruff, Troster, Barth, Koffler, et al, 2005;Larrabee, 2005). Slick, Sherman, e Iverson (1999) apontam, neste âmbito, critérios de diagnóstico, em parte sobreponíveis ao apontado pela DSM-IV-TR, para Simulação de Perturbação Neurocognitiva Possível, Provável e Definitiva, que incluem: presença de incentivos externos substanciais, evidências nos resultados em testes neuropsicológicos, indícios de exagero de sintomas no auto-relato do sujeito, não devendo estes comportamentos de simulação ser melhor explicados por doença psiquiátrica, neurológica ou desenvolvimental (para uma redefinição do contributo dos testes psicométricos para o diagnóstico de Simulação de Perturbação Neurocognitiva Provável, cf.…”