Tuesday, 19 August 2003
This presentation is part of : Tuesday Poster Sessions

PB-069 The Clock Drawing Test Can Be a Single Screening Test? Results' Correlation with the Cambridge Cognitive Examination (CAMCOG) for Dementia

José Eduardo Martinelli1, Ivan Aprahamian1, Renata Vasconcellos Regazzini1, and Benito Pereira Damasceno2. (1) Geriatrics and Gerontology Division, Faculdade de Medicina de Jundiaí, Jundiaí, Brazil, (2) Neurology Department, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil

Introduction: The CAMDEX (Roth et al., 1978) is a structured interview for diagnoses of mental disturbs (dementia, delirium, depression and others) in the elderly. The CAMCOG is one of the test sessions and comprehends the clock drawing test (CDT) with only 3 point to the final score. The CAMCOG has 92% of sensibility and 96% of specificity. Its mean duration is 40 minutes. The CDT is a screening test to detect dementia. There are many validated scales to interpret the clock with a mean sensibility and specificity of 85% (Shulman, 2000). This test takes 3.5 minutes. There is some discussion if the CDT can be a single screening test or is necessary to have one more test like Mini Mental Status Examination (MMSE; Folstein et al., 1975) to achieve a good accuracy for dementia (Heun et al., 1998). Objectives: To verify the accuracy and diagnostic concordance between the CAMCOG and the CDT using one validated scale to interpret the clock. Material and Methods: Ninety patients with probable Alzheimer’s disease according to NINCDS-ADRDA (McKhann et al., 1984) were submitted to CAMCOG, CDT and MMSE in a cross-sectional study. The CAMCOG cut-off point used for dementia was 79. The CDT was classified by two raters using Shulman modified scale (Shulman et al., 1993). The conformity between the tests (CDT versus CAMCOG; MMSE versus CAMCOG; and CDT versus MMSE) was evaluated by kappa (k) concordance coefficient and the accuracy of the tests was evaluated by qui-square and Fisher test (when necessary). Results: There were 32 (35.6%) male and 58 (64.4%) female. The mean age was 77.27 years (±6.37 SD). The inter-rater reliability coefficient was good (k=0.75). The concordance between CDT and CAMCOG was weak to intermediate (k=0.360) with a high sensitivity (SE) of 91.18%, a low specificity (ES) of 40.91% and a good accuracy (AC) of 78.89%. The concordance between CDT and MMSE was weak (k=0.103). The MMSE compared with CAMCOG had intermediate concordance (k=0.445) with good SE (77.94%), ES (72.73%) and AC (76.67%). Conclusion: The concordance results between the CDT and CAMCOG reveal an excellent sensitivity for a screening test but a low specificity that cannot permit its usage as a single test. The CDT analysis is not scale-dependent according to the literature (Shulman, 2000) and the chosen scale cannot have influence over the concordance between the tests. By the other hand, MMSE had a good correlation with CAMCOG as we can see in current literature (Tombauch and Mclntyre, 1992). The positive performance of MMSE caused a weak concordance with CDT showing that MMSE is a more secure screening test.

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