***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective : To develop a short cognitive test for screening mild cognitive impairment ( MCI ) in Hong Kong Chinese older adults . Methods : The Chinese Abbreviated MCI ( CAMCI ) test was developed with a multistage process . In phase 1 , a short version of the cognitive test comprising a 1-min animal fluency test and a 10-min delayed word list recall was developed and tested in 578 volunteers ( community-dwelling active elderly persons ) . In phase 2 , the CAMCI test was vali date d in an independent and r and omly recruited sample of 459 participants in a community survey . Additionally , the predictive significance of the CAMCI test was evaluated in a group of 196 subjects assessed in phase 1 for conversion to clinical dementia at 20 months ’ follow-up . The discriminating power of the CAMCI test in differentiating MCI from normal control ( NC ) and mildly demented subjects was compared with Mini Mental State Examination ( MMSE ) and Alzheimer ’s Disease Assessment Scale-Cognitive ( ADAS-Cog ) subscales . Results : The CAMCI test was found to have high discriminating power in differentiating NC from MCI and mildly demented subjects in the phase 1 volunteer sample . The receiver operating characteristics ( ROC ) revealed an area under the curve ( AUC ) of 0.91 . The ROC were further vali date d in the phase 2 sample . The AUC of the CAMCI test was compared with MMSE and ADAS-Cog subscales . The short MCI test was comparable to the ADAS-Cog subscale in discriminating NC from MCI and demented subjects ( χ2 test , p = n.s . ) . Logistic regression analysis was carried out to determine significant baseline predictors for conversion to dementia at phase 3 follow-up . Both ADAS-Cog total [ Exp(B ) = 1.115 , p = 0.028 ] and CAMCI [ Exp(B ) = 0.88 , p = 0.045 ] scores were significant predictors for dementia status at follow-up . Conclusion : The CAMCI test is able to discriminate NC from MCI and mild dementia in Hong Kong Chinese older adults . Its potential for large-scale community screening for early detection of cognitive impairment in late life should be emphasized and explored Background / Aims : To prospect ively follow up a group of  amnesic patients at risk for Alzheimer ’s disease ( AD ) , to characterize a group of patients whose features were intermediate between amnesic mild cognitive impairment ( aMCI ) and probable AD , prodromal AD ( Prd-AD ) , and to investigate if these patients were at higher risk for AD conversion . Methods : A total of 109 subjects were assessed by neuropsychological evaluation and by 1H magnetic resonance spectroscopy ( 1H-MRS ) :  27 controls , and 16 aMCI , 34 probable AD and 32 Prd-AD patients . Results : Episodic memory and frontal test scores result ed lower in Prd-AD compared to aMCI patients . Prd-AD patients obtained significantly higher scores than AD ones in language , perception , praxis and frontal functions . Although Prd-AD and AD patients had distinct 1H-MRS features from aMCI ones , there were no 1H-MRS differences between Prd-AD and AD patients . The AD annual conversion rate after 1 year of follow-up for Prd-AD ( 57.1 % ) was higher than in aMCI patients ( 20 % ; p < 0.01 ) . A logistic regression , in which all amnesic patients were treated as a single group , showed that the Visual Memory Test was a significant neuropsychological predictor for AD conversion . Conclusions : Prd-AD patients are a clinical ly distinguishable group , with distinct neuropsychological and 1H-MRS features and a higher conversion rate to probable AD than aMCI patients BACKGROUND Subjects with a mild cognitive impairment ( MCI ) have a memory impairment beyond that expected for age and education yet are not demented . These subjects are becoming the focus of many prediction studies and early intervention trials . OBJECTIVE To characterize clinical ly subjects with MCI  cross-sectionally and longitudinally . DESIGN A prospect i ve , longitudinal inception cohort . SETTING General community clinic . PARTICIPANTS A sample of 76 consecutively evaluated subjects with MCI were compared with 234 healthy control subjects and 106 patients with mild Alzheimer disease ( AD ) , all from a community setting as part of the Mayo Clinic Alzheimer 's Disease Center/Alzheimer 's Disease Patient Registry , Rochester , Minn. MAIN OUTCOME MEASURES The 3 groups of individuals were compared on demographic factors and measures of cognitive function including the  Mini-Mental State Examination , Wechsler Adult Intelligence Scale-Revised , Wechsler Memory Scale-Revised , Dementia Rating Scale , Free and Cued Selective Reminding Test , and Auditory Verbal Learning Test .  Clinical classifications of dementia and AD were determined according to the Diagnostic and Statistical Manual of Mental Disorders , Revised Third Edition and the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer 's Disease and Related Disorders Association criteria , respectively . RESULTS The primary distinction between control subjects and subjects with MCI was in the area of memory , while other cognitive functions were comparable . However , when the subjects with MCI were compared with the patients with very mild AD , memory performance was similar , but patients with AD were more impaired in other cognitive domains as well . Longitudinal performance demonstrated that the subjects with MCI declined at a rate greater than that of the controls but less rapidly than the patients with mild AD . CONCLUSIONS Patients who meet the criteria for MCI can be differentiated from healthy control subjects and those with very mild AD . They appear to constitute a clinical entity that can be characterized for treatment interventions Background : Magnetic resonance diffusion tensor imaging ( DTI ) shows promise in the early detection of microstructural pathophysiological changes in the brain . Objectives : To measure microstructural differences in the brains of participants with amnestic mild cognitive impairment ( MCI ) compared with an age-matched control group using an optimised DTI technique with fully automated image analysis tools and to investigate the correlation between diffusivity measurements and neuropsychological performance scores across groups . Methods : 34 participants ( 17 participants with MCI , 17 healthy elderly adults ) underwent magnetic resonance imaging (MRI)-based DTI .  To control for the effects of anatomical variation , diffusion images of all participants were registered to st and ard anatomical space . Significant statistical differences in diffusivity measurements between the two groups were determined on a pixel-by-pixel basis using gaussian r and om field theory . Results : Significantly raised mean diffusivity measurements ( p<0.001 ) were observed in the left and right entorhinal cortices ( BA28 ) , posterior occipital – parietal cortex ( BA18 and BA19 ) , right parietal supramarginal gyrus ( BA40 ) and right frontal pre central gyri ( BA4 and BA6 ) in participants with MCI . With respect to fractional anisotropy , participants with MCI had significantly reduced measurements ( p<0.001 ) in the limbic parahippocampal subgyral white matter , right thalamus and left posterior cingulate . Pearson ’s correlation coefficients calculated across all participants showed significant correlations between neuropsychological assessment scores and regional measurements of mean diffusivity and fractional anisotropy . Conclusions : DTI-based diffusivity measures may offer a sensitive method of detecting subtle microstructural brain changes associated with pre clinical Alzheimer ’s disease Summary OBJECTIVE : The goals of this study were to determine the annual conversion rate to Alzheimer disease ( AD ) among patients reporting memory problems , including a subgroup with amnestic mild cognitive impairment ( aMCI ) , and to investigate the predictive value of neurocognitive testing for future dementia . METHODS : A prospect i ve study was carried out in an outpatient memory clinic . One hundred and seven patients underwent a clinical examination and completed a battery of st and ard cognitive tests at study entry and two years later . The conversion rate to clinical ly manifested AD two years later was investigated , and sensitivity , specificity , receiver operating characteristics ( AUC ) , positive predictive value and negative predictive value for each neuropsychological test were determined . RESULTS : We found an annual rate of conversion to AD of 6.5 % among patients reporting memory decline in the setting of our clinic . Specifically , patients with aMCI had an annual conversion rate of approximately 20 % . The annual conversion rate for patients reporting memory problems but showing no memory deficit at memory testing was approximately 3 % . Receiver operating characteristics ( AUC ) of the neuropsychological tests ranged from 0.60 to 0.94 . CONCLUSIONS : Patients with aMCI have 8.6-fold higher odds of developing AD compared with patients without evident memory impairment on neuropsychological testing . Although the risk of developing AD among patients without objective memory decline is small , some patients in this group still convert to AD , and therefore , close clinical monitoring of patients is necessary . ZusammenfassungZIEL : Ziel der vorliegenden Studie war die Bestimmung der jährlichen Konversionsrate von Patienten mit subjektiver Gedächtnisbeeinträchtigung zur Alzheimerkrankheit unter Berücksichtigung der amnestischen Milden Kognitiven Störung ( aMCI ) . Die Wertigkeit zur Vorhersage der Konversion durch einzelne neuropsychologische Testverfahren wurde ebenfalls untersucht . METHOD IK : I m Rahmen einer Gedächtnisambulanz wurde eine prospektive Studie durchgeführt . 107 Patienten wurden in die Studie inkludiert . Alle Patienten durchliefen eine neurologische und eine neuropsychologische Untersuchung am Beginn der Studie und nach zwei Jahren am Ende der Studie . Einerseits wurde die Konversionsrate zur Alzheimerkrankheit untersucht , und and erseits wurden einige Kennwerte der Kriteriumsvalidität ( Sensitivität , Spezifität , Receiver Operating Characteristics [ AUC ] , Positive Predictive Value , Negative Predictive Value ) einzelner neuropsychologischer Testverfahren zur Vorhersage der Alzheimerkrankheit bestimmt . RESULT AT : Wir f and en eine jährliche Konversionsrate von 6,5 % für Patienten , die eine Beeinträchtigung der Gedächtnisfunktionen berichteten . Patienten mit aMCI hatten eine jährliche Konversionsrate von ungefähr 20 % . Die jährliche Konversionsrate von Patienten mit subjektiver Gedächtnisbeeinträchtigung ohne testpsychologisch nachweisbare Gedächtnistörung  lag bei ungefähr 3 % . Receiver operating characteristics ( AUC ) für einzelne neuropsychologische Verfahren lagen zwischen 0,60 und 0,94 . KONKLUSION : Patienten mit aMCI haben , i m Vergleich zu Patienten ohne neuropsychologisch fassbare Gedächtnisstörung , eine 8,6-fache Wahrscheinlichkeit , innerhalb von zwei Jahren eine klinisch manifeste Alzheimerkrankheit zu entwickeln . Obwohl die Wahrscheinlichkeit für Patienten ohne neuropsychologisch fassbare Gedächtnisstörung , innerhalb von zwei Jahren eine Alzheimerkrankheit zu entwickeln , gering ist , konvertieren einige wenige Patienten doch zur Alzheimerkrankheit . Engmaschige Kontrolluntersuchungen sind deshalb notwendig Objective . To design a brief cognitive screener with acceptable sensitivity and specificity for identifying subjects with cognitive impairment Design . Cohort one is assembled from a community-based survey coupled with a second-stage diagnostic evaluation using formal diagnostic criteria for dementia . Cohort two is assembled from referrals to a specialty clinic for dementing disorders that completed the same diagnostic evaluation . Setting . Urban neighborhoods in Indianapolis , Indiana and the Indiana Alzheimer Disease Center . Patients . Cohort one consists of 344 community-dwelling black persons identified from a r and om sample of 2212 black persons aged 65 and older residing in Indianapolis ; cohort two consists of 651 subject referrals to the Alzheimer Disease Center . Measurements . Formal diagnostic clinical assessment s for dementia including scores on the  Mini-mental state examination ( MMSE ) , a six-item screener derived from the MMSE , the Blessed Dementia Rating Scale ( BDRS ) , and the Word List Recall .  Based on clinical evaluations , subjects were categorized as no cognitive impairment , cognitive impairment-not demented , or demented . Results . The mean age of the community-based sample was 74.4 years , 59.4 % of the sample were women , and the mean years of education was 10.1 . The prevalence of dementia in this sample was 4.3 % and the prevalence of cognitive impairment was 24.6 % . Using a cut-off of three or more errors , the sensitivity and specificity of the six-item screener for a diagnosis of dementia was 88.7 and 88.0 , respectively . In the same sample , the corresponding sensitivity and specificity for the MMSE using a cut-off score of 23 was 95.2 and 86.7 . The performance of the two scales was comparable across the two population s studied and using either cognitive impairment or dementia as the gold st and ard . An increasing number of errors on the six-item screener is highly correlated with poorer scores on longer measures of cognitive impairment . Conclusions . The six-item screener is a brief and reliable instrument for identifying subjects with cognitive impairment and its diagnostic properties are comparable to the full MMSE . It can be administered by telephone or face-to-face interview and is easily scored by a simple summation of errors BACKGROUND  Mild cognitive impairment ( MCI )  is considered to be a transitional 
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Sensitivities of the full domain measures were universally high , but information about their specificity against psychiatric and non-progressive neurological conditions and predictive validity is lacking .
Several cognitive screening instruments afford the clinician the ability to detect MCI , early AD , and in some cases non-AD dementia , but they can not currently be used to make reliable inferences about the course and eventual outcome of MCI