The concise cognitive test for dementia screening: Reliability and effects of demographic variables as compared to the mini mental state examination

Background: The Mini Mental State Examination (MMSE) is widely used for dementia screening but has several shortcomings such as prominent ceiling effects, inadequate sensitivity to mild cognitive impairment, and uneven sampling of the major cognitive domains.
Aims: In this study, we pilot a new dementia screening test - the Concise Cognitive Test (CONCOG) - designed to overcome the above short comings and describe the reliability measures and age, education, and gender effects. The CONCOG has a total score of 30, and has subtests for orientation, naming, registration, free recall and recognition of four words, semantic verbal fluency and copying.
Patients and Methods: Participants were screened to exclude those with any neurological or psychiatric disease, simultaneously administered the CONCOG, and a Hybrid Mini Mental State Examination (HMMSE) adapted from Folstein′s MMSE and Ganguli′s Hindi Mental State Examination.
Results: The study sample had 204 subjects over the age of 60 years with a mean of 73 years and education level of 8 (4.5) years. Internal consistency for the CONCOG (Cronbach′s alpha) was 0.74, inter-rater reliability (Kendall′s tau-b) was 0.9, and the one-month test-retest reliability (Kendall′s tau-b) was 0.7. Age and education level, but not gender, significantly influenced performance on both scales. Although the influence of age on the two scales was to a similar degree, the HMMSE was more affected by education than the CONCOG. Of 204 subjects, only 12 (5.7%) subjects obtained the maximum score on the CONCOG compared with 30 (14.1%) subjects on the HMMSE. The CONCOG took less than 10 minutes to complete in this sample. Age and education stratified norms are presented for the CONCOG.
Conclusions: The CONCOG is a reliable cognitive screening measure. It has negligible ceiling effects, is less influenced by education compared with the HMMSE, and offers subscale scores for the major cognitive domains.