Effort test performance in clinical acute brain injury, community brain injury, and epilepsy populations.

Effort tests have become commonplace within medico-legal and forensic contexts and their use is rising within clinical settings. It is recognized that some patients may fail effort tests due to cognitive impairment and not because of poor effort. However, investigation of the base rate of failure among clinical populations other than dementia is limited. Forty-seven clinical participants were recruited and comprised three subgroups: acute brain injury (N = 11), community brain injury (N = 20), and intractable epilepsy (N = 16). Base rates of failure on the Word Memory Test (WMT; Green, 2003 ) and six other less well-validated measures were investigated. A significant minority of patients failed effort tests according to standard cutoff scores, particularly patients with severe traumatic brain injury and marked frontal-executive features. The WMT was able to identify failures associated with significant cognitive impairment through the application of profile analysis and/or lowered cutoff levels. Implications for clinical assessment, effort test interpretation, and future research are discussed.