The MCI Index

The Cognistat Assessment System (CAS-II), Cognistat Active Form, Cognistat Five and Cognistat Five Active Form incorporate a 7-point index for estimating the risk of Mild Cognitive Impairment (MCI) and dementia.  The value reflects both the degree of cognitive impairment and the increasing likelihood or risk of MCI or a dementia syndrome.  The first four MCI Index values from 0 to 3 address the probability of the presence of MCI.  They range from no indication of cognitive impairment to strongly suggesting an MCI condition.  As the degree of cognitive impairment increases, the index values address the probability of a possible dementia syndrome.  Index values from 4 to 6 range from 4 which “raises the question of dementia” to 6 which “strongly suggests a dementia syndrome.” 

  MCI Index = 0: no indication of cognitive impairment
  MCI Index = 1: raises the question of MCI
  MCI Index = 2: suggests MCI
  MCI Index = 3: strongly suggests MCI
  MCI Index = 4: raises the question of a dementia syndrome
  MCI Index = 5: suggests a dementia syndrome
  MCI Index = 6: strongly suggests a dementia syndrome

The MCI Index levels are derived from the patient’s performance on the subtests for Memory and Constructions and are adjusted for Age and Level of Education.  The Index is designed to provide guidance regarding diagnostic questions of mild cognitive impairment or dementia.  It is not intended for use in cases with isolated and more specific cognitive deficits such as amnestic or aphasic disorders nor as a stand-alone tool to diagnose either MCI or dementia.

MCI and dementia diagnoses depend upon a clinical judgment that incorporates the historical and clinical context of the individual patient, in addition to the results of cognitive testing.  The clinical context includes the presence of any previously diagnosed medical or psychiatric conditions, the possible impact of prescribed medications, and the influence of other factors such as pain, sleep deprivation and visual impairment.