Serial sevens

Serial sevens, counting down from one hundred by sevens, is a clinical test used to test mental function; for example, to help assess mental status after possible head injury or in suspected cases of dementia. It forms part of the Mini mental state examination.

On its own, the inability to perform 'serial sevens' is not diagnostic of any particular disorder or impairment, but is generally used as a quick and easy test of concentration and memory in any number of situations where clinicians suspect that these cognitive functions might be affected.

Similar tests include serial threes where the counting downwards is done by threes, reciting the months of the year in reverse order, or spelling 'world' backwards.