Performance validity in clinical neuropsychological assessment: base rates, impact of feedback, and relevance to outcomes

The studies conducted in this dissertation demonstrated that invalid performance is prevalent in a substantial minority of adult patients seen for routine clinical care. The relevance of invalid performance extends beyond diagnosis and encompasses (a) management strategies for patients who show indications of noncredible performance, and (b) adherence to subsequent treatments. Our studies provide clinicians with more knowledge, insights, and practical guidance about performance validity assessment in routine clinical care. By offering practical tools for improving the determination of performance validity status and by clarifying its importance, clinicians may feel more comfortable integrating the proposed validity assessment guidelines into their daily practices. Ultimately, patients may benefit from these developments as this may lead to a specific clinical focus on noncredible performance, rather than overlooking the possibility of non-credible performance, dismissing (or the incorrect interpretation of) PVT failure, or losing empathy and abandoning attempts to provide clinical aid.