A Normative Study of the Digit Span in an Educationally Diverse Elderly Population

OBJECTIVE: The purpose of this study was to explore the effect of demographic variables on Digit Span test (DS) performance in an educationally diverse elderly population and to provide normative information. METHODS: The DS was administered to 784 community-dwelling volunteers aged 60-90 years with an educational history of from zero to 25 years of full-time education. People with serious neurological, medical and psychiatric disorders (including dementia) were excluded. RESULTS: Age, education and gender were found to be significantly associated with performance on the DS. Based on the results obtained, DS norms were stratified by age (2 strata), education (3 strata), and gender (2 strata). CONCLUSION: Our results on DS performance suggest that both attention and working memory are influenced by age, education and gender. The present study provides reasonably comprehensive normative information on the DS for an educationally diverse elderly population.

A Normative Study of an Executive Clock Drawing Task(CLOX) in Korean Elderly / 신경정신의학

OBJECTIVES: The CLOX (an executive clock drawing task) consists of an unprompted task that is sensitive to executive function (CLOX1) and a copied version that is more dependent on visuoconstructive function (CLOX2). This study aimed to explore the effects of age, education, and gender on the performance of the CLOX and to provide normative information on the test in the Korean elderly. METHODS: We administered the CLOX to 608 community-dwelling healthy volunteers aged 60-90, excluding people with serious neurological, medical, and psychiatric disorders, including dementia. Multiple linear regression analysis was performed to assess the relative contributions of the demographic factors to the CLOX scores. RESULTS: Education had a considerable influence on performance of both CLOX1 and CLOX2. Age and gender also had significant effect on both. There were significant interactions between education and gender for both CLOX1 and CLOX2. We also found interactions between education and age on CLOX2. Based on these results, we created normative data for the CLOX, stratified by age (60-74 and 75-90 years), education (0-3, 4-9, and 10+ years), and gender. CONCLUSION: Our normative data, based on a large, healthy elderly population, provides accurate reference information on CLOX performance and should be very useful for proper interpretation of CLOX scores in the Korean elderly.

Reliability and Validity of the Korean Version of Short Blessed Test (SBT-K) as a Dementia Screening Instrument / 신경정신의학

We aimed to develop the Korean version of Short Blessed test (SBT-K) by analyzing its reliability and validity, showing its usefulness as a dementia screening instrument. The translation, including back translation procedure, was carried out, keeping the basic structure of SBT. SBT-K. The Korean Version of Blessed Dementia Scale-Activity of Daily Living (BDS-ADL-K) and Clinical Dementia Rating Scale (CDR) were administered to 224 dementia patients and 191 control subjects, and The Korean Version of Consortium to Establish a Registry of Alzheimer's Disease-Mini-Mental State Examination (CERAD-MMSE-K) was to 157 patients and 167 controls. The correlation of SBT-K scores between two raters, correlation between the test and retest after one month, and its internal consistency were analyzed. To verify the concurrent validity of SBT-K, its correlation with each test: CERAD-MMSE-K, BDS-ADL-K, and CDR was analyzed. The sensitivity and specificity for each cut-off point of SBT-K were calculated and the Receiver Operator Characteristic (ROC) curve analysis was done to get its optimal cut-off point. SBT-K was found to have significantly high internal consistency, inter-rater reliability, and test-retest reliability. The significant correlation of SBT-K with each test described above was also shown. Its optimal cut-off point was estimated as 10/11, and the sensitivity and specificity were 0.85 and 0.90, respectively. The ROC curve analysis indicated that the diagnostic efficiency of SBT-K was comparable with CERAD-MMSE-K. We conclude that SBT-K has not only high reliability and validity, but also usefulness as a screening instrument for dementia.