frontal assessment battery frontal assessment battery the frontal assessment battery (fab) is a short screening test to evaluate executive function (ef). frontal assessment batterypurposeevaluate executive function format fab is a battery of tests, consisting of six subtests, that takes about 10 minutes and is designed as a short bedside assessment of executive function. applications fab is useful in the differential diagnosis of neurological diseases including parkinson's disease, corticobasal degeneration, frontotemporal dementias, alzheimer's disease, huntington's disease, progressive supranuclear palsy, and dementia with lewy bodies. development fab was developed by dubois et al. in 2000 and became a widely used tool.