Questioning What We Thought We Knew: Commentary on Leonhard's Performance Validity Assessment Articles.

Neuropsychologists have long understood that valid examinee performance is needed in order to understand the constructs of interest that are at the heart of clinical and forensic evaluations. The assessment of performance validity has evolved over time, from very rudimentary and subjective clinical impressions of examinee task engagement to psychometrically based, multi-method, algorithm-driven, and consensus-informed approaches. Christoph Leonhard has further advanced that evolution in a meaningful way, forcing us to reconsider much of what we thought we knew about the psychometric assessment of performance validity. Although a structured, systematic, and objective approach to validity assessment is necessary, Leonhard has brought to our attention some significant concerns that need to be addressed. This commentary describes professional, ethical, and legal implications of Leonhard's articles. Through an ongoing process of examining, revising, and improving our methods and procedures, we will be better positioned to provide services of value to those we serve. Leonhard has provided an opportunity for us to do just that.