Sensitivity and specificity of the Bamberg Dementia Screening Test’s (BDST) full and short versions: brief screening instruments for geriatric patients that are suitable for infectious environments

Abstract

Background: Currently, many patients suffering from dementia do not have a diagnosis when admitted to geriatric hospitals. This is the case despite an increased risk of complications affecting the length of stay and outcome. Unfortunately, many dementia screening tests cannot be used on geriatric inpatients, who are often bedridden. Therefore, we aimed at evaluating the diagnostic accuracy of a small battery of bedside tasks that require minimal vision and fine motor skills in patients with suspected dementia. Methods: In this prospective study, the Bamberg Dementia Screening Test (BDST) was administered to a consecutive series of 1295 patients referred for neuropsychological testing. The diagnosis of dementia was confirmed in 1159 and excluded in 136 patients. Sensitivity and specificity for the first subtest (ultra-short form), the first two subtests (short form), and the total score of the BDST were obtained via receiver operating characteristic curves and compared with the sensitivity and specificity values of the Mini-Mental Status Examination (MMSE). Results: The overall diagnostic quality of the BDST was superior to the MMSE for mild Alzheimer’s dementia (sensitivity and specificity =.94 (95% CI.92 to.96) and.82 (95% CI.75 to.88) vs.79 (95% CI.76 to.83) and.88 (95% CI.82 to.93)) as well as for other subtypes of mild dementia (sensitivity and specificity =.91 (95% CI.88 to.94) and.82 (95% CI.75 to.88) vs.72 (95% CI.67 to.76) and.88 (95% CI.82 to.93)). Even the short form of the BDST was comparable to the MMSE regarding sensitivity and specificity. For moderate dementia, it was possible to identify dementia cases with sufficient and excellent diagnostic quality by using the ultra-short and the short form. Conclusions: The BDST is able to detect dementia in geriatric hospital settings. If the adaptive algorithm is used, administration time can be reduced to less than 2 min in most cases. Because no test materials have to be exchanged, this test is particularly suitable for infectious environments where contact between the examiner and the person being tested should be minimized.