Background: The main purpose of this study was to correlate a newly developed, simple, but comprehensive screening test for dementia called the Self Test (ST) with the Mini-mental State Examination (MMSE), and establish the reliability and validity of the ST.
Methods:The ST was administered to 42 consecutive new referrals to the memory clinic at the Cole Neuroscience Center, University of Tennessee Medical Center (UTMC), Knoxville, TN, U.S.A. and 41 age-matched control subjects at regular intervals over a 12-month period.
Results:The total ST scores correlated well with cognitive severity as measured by the MMSE (r = 0.71, p<0.01). The area under the receiver-operating characteristic curve (AUROCC) in the group of patients with Alzheimer's disease (AD) with less than a high school education was 0.80, and 0.89 in those with at least a high school education. Reliability analysis showed a mean inter-item correlation of 0.31 for patients with AD, and 0.47 for normal participants. Cronbach's α was calculated to be 0.70 for the AD group. Test–retest reliability was determined using intraclass correlation coefficients (ICC = 0.93, p<0.01).
Conclusions: The ST is an internally consistent, reliable and valid screening test for cognitive impairment in persons exhibiting early symptoms of dementia. In addition, the ST requires minimal nonprofessional supervision and may be administered by an untrained person.