Recent work has demonstrated the Montreal Cognitive Assessment (MoCA) and Visual Cognitive Assessment Test (VCAT)1 to be superior to MMSE in detecting cognitive impairment. However, the diagnostic performance of these cognitive screening tools is not well known in patients with young onset dementia (YOD) of the Alzheimer's type. Patients under the age of 65-year-old with memory complaints were recruited from the National Neuroscience Institute in a prospective study. Demographics, cognitive data and biomarker data including cerebrospinal fluid (CSF) were collected. Cognitive tests were administered by trained psychologists and CSF Amyloidβ, total tau and phosphor-tau were performed using ELISA techniques. Sensitivity (Se), Specificity (Sp), Positive Predicting Value (PPV), Negative Predicting Value (NPV) were calculated for MMSE, MoCA and VCAT using a 2x2 table where patients were classified by their CSF results based on the Tau/Amyloidβ Duit's score2(CSF negative= ≤0.52, CSF positive= >0.52,) and whether they were cognitively impaired based on a validated cut-off on the respective screening tools. VCAT individual domain scores were also correlated with domain-specified tests like the WMS story recall, REYS copy task, ADAS cancellation task, Boston Naming and Colour Trials 2. A total of 29 Young Dementia patients with CSF Amyloidβ and tau were recruited, and 16 of them fulfilled Duit's criteria for AD. Their mean (SD) age was 57.07 (6.65), mean (SD) year of education was 11.62 (4.18). 44.8% were males and 75.9% were Chinese. MMSE attained the lowest Se of 68.75% while MoCA and VCAT were quite comparable on Se and PPV at 93.75% vs 87.50 % and 85.71% vs 84,62% respectively, VCAT performed the most favorably in Sp (84.62%) and PPV (87.50%). VCAT individual domains of memory (r=0.836, p<0.001), visuo-spatial (r=0.746, p<0.001), language (r=0.732, p<0.001) and executive function (r=0.793, p<0.001) showed significant correlation to the other domain-specific tests. Our results support that VCAT will be a useful and effective tool in the diagnosis of Young Onset dementia. The high performance of the VCAT in this cohort is likely related to the large range of cognitive domains tested, including visual perception and agnosia. 1 Kandiah N, et al. Early detection of dementia in multilingual populations: Visual Cognitive Assessment Test (VCAT). Journal of Neurology, Neurosurgery & Psychiatry. 2016 Feb 1;87(2):156–60. 2 Duits FH, et al. The cerebrospinal fluid “Alzheimer profile”: easily said, but what does it mean? Alzheimer's & Dementia. 2014 Nov 30;10(6):713–23.