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Background More sensitive and less burdensome efficacy end points are urgently needed to improve the effectiveness of clinical drug development for Alzheimer disease (AD). Although conventional end points lack sensitivity, digital technologies hold promise for amplifying the detection of treatment signals and capturing cognitive anomalies at earlier disease stages. Using digital technologies and combining several test modalities allow for the collection of richer information about cognitive and functional status, which is not ascertainable via conventional paper-and-pencil tests. Objective This study aimed to assess the psychometric properties, operational feasibility, and patient acceptance of 10 promising technologies that are to be used as efficacy end points to measure cognition in future clinical drug trials. Methods The Method for Evaluating Digital Endpoints in Alzheimer Disease study is an exploratory, cross-sectional, noninterventional study that will evaluate 10 digital technologies’ ability to accurately classify participants into 4 cohorts according to the severity of cognitive impairment and dementia. Moreover, this study will assess the psychometric properties of each of the tested digital technologies, including the acceptable range to assess ceiling and floor effects, concurrent validity to correlate digital outcome measures to traditional paper-and-pencil tests in AD, reliability to compare test and retest, and responsiveness to evaluate the sensitivity to change in a mild cognitive challenge model. This study included 50 eligible male and female participants (aged between 60 and 80 years), of whom 13 (26%) were amyloid-negative, cognitively healthy participants (controls); 12 (24%) were amyloid-positive, cognitively healthy participants (presymptomatic); 13 (26%) had mild cognitive impairment (predementia); and 12 (24%) had mild AD (mild dementia). This study involved 4 in-clinic visits. During the initial visit, all participants completed all conventional paper-and-pencil assessments. During the following 3 visits, the participants underwent a series of novel digital assessments. Results Participant recruitment and data collection began in June 2020 and continued until June 2021. Hence, the data collection occurred during the COVID-19 pandemic (SARS-CoV-2 virus pandemic). Data were successfully collected from all digital technologies to evaluate statistical and operational performance and patient acceptance. This paper reports the baseline demographics and characteristics of the population studied as well as the study's progress during the pandemic. Conclusions This study was designed to generate feasibility insights and validation data to help advance novel digital technologies in clinical drug development. The learnings from this study will help guide future methods for assessing novel digital technologies and inform clinical drug trials in early AD, aiming to enhance clinical end point strategies with digital technologies. International Registered Report Identifier (IRRID) DERR1-10.2196/35442

Objective: This study examined the effects of the OutSMARTers program on social skills, self-regulation, and executive functions compared with a Waitlist group and a parent training program. Method: Participants were 41 children with ADHD, aged 8 to 10 years. All groups were assessed with behavioral checklists and neuropsychological measures at baseline and post-treatment. The two treatment groups were reassessed with behavioral checklists after 3 months. Results: Findings revealed decreased ADHD symptoms, improved social skills, and better emotion regulation at post-treatment for the OutSMARTers compared with the Waitlist group on subjective measures. No differences were found on objective tasks or between the OutSMARTers and Parent groups after treatment but both treatment groups showed some improvement. In addition, most of the post-treatment changes were maintained for both groups 3 months later. Conclusion: The results indicate that the OutSMARTers program seems to benefit children with ADHD, but further research and treatment development is needed.

Numerous statistically derived composite measures have recently been proposed as clinical outcome assessments (COAs) for clinical trials in the early stages of Alzheimer disease. Critical Path Institute's Coalition Against Major Diseases (CAMD) advanced a proposed statistically derived composite measure to regulatory agencies with the goal of qualifying it as a COA for pre-dementia trials. In response to FDA's requirement to demonstrate that proposed COAs are meaningful to patients, this project aimed to identify the most important cognition-related concerns patients and informants report early in the disease and determine how this information maps to what is assessed by several statistically derived composite measures.Leveraging qualitative research completed by Critical Path Institute's Patient-Reported Outcome Consortium, CAMD utilized a summary report that included frequency grids of reported concerns of amnestic mild cognitive impairment patients and their informants, as well as the narrative transcripts from focus groups. Transcripts were reviewed and analyzed to identify which cognitive domains the patient- and informant-reported concerns mapped onto. The results were then compared to see how well these cognitive domains were represented in various statistically derived composite measures.The patient- and informant-reported concerns primarily mapped to the cognitive domains of episodic memory and, secondarily, orientation and language. Depending on the specified composite, there were varying levels of alignment between their subcomponents and these cognitive domains.Through secondary analyses of existing qualitative data, this study examined several statistically derived composite measures and found that they generally capture cognitive domains that reflect aspects of day-to-day functioning that patients and informants consider meaningful.

Publisher's version (útgefin grein), Introduction We have previously reported that retinal vessel oxygen saturation is increased in mild-to-moderate dementia of Alzheimer's type when compared with healthy individuals. Mild cognitive impairment (MCI) is the predementia stage of the disease. The main purpose was to investigate if these changes are seen in MCI. Methods Retinal vessel oxygen saturation was measured in 42 patients with MCI and 42 healthy individuals with a noninvasive retinal oximeter, Oxymap T1. The groups were paired according to age. Results Arteriolar and venular oxygen saturation was increased in MCI patients compared to healthy individuals (arterioles: 93.1 ± 3.7% vs. 91.1 ± 3.4%, P = .01; venules: 59.6 ± 6.1% vs. 54.9 ± 6.4%, P = .001). Arteriovenous difference was decreased in MCI compared to healthy individuals (33.5 ± 4.5% vs. 36.2 ± 5.2%, P = .01). Discussion Increased retinal vessel oxygen saturation and decreased arteriovenous difference in MCI could reflect less oxygen extraction by retinal tissue. This indicates that retinal oxygen metabolism may be affected in patients with MCI., Olof Birna Olafsdottir received a grant from the Icelandic Centre for Research. The sponsor did not have any role in the study design; in the collection, analysis, and interpretation of the data; in the writing of the report, and in the decision to submit the article for publication.

Stimulation of nicotinic cholinergic systems has been shown to alleviate ADHD symptoms and to improve cognitive performance. AZD1446 is a selective α4β2* nicotinic acetylcholine receptor agonist with potential effect on the symptoms of ADHD.The purpose of this study is to evaluate the efficacy, safety, and pharmacokinetics of AZD1446 in adults with ADHD treated for 2 weeks.This was a randomized, double-blind, placebo-controlled crossover trial. Participants were 79 adults with ADHD, grouped according to their use of nicotine-containing products. Nicotine non-users received placebo and two of three AZD1446 treatment regimens (80 mg tid, 80 mg qd, 10 mg tid). Nicotine users received placebo, AZD1446 80 mg tid and 80 mg qd. Efficacy measures included the Conners' Adult ADHD Rating Scale and cognitive measures of immediate and delayed verbal episodic memory, learning, attention, working memory, executive functioning, and spatial problem solving (CogState computerized test battery).There was no significant effect of AZD1446 on any of the clinical scores irrespective of dose, schedule, or concomitant use of nicotine products. A statistically significant improvement was seen on the Groton Maze Learning Task, a measure of executive functioning, in nicotine non-users after treatment with AZD1446 80 mg qd.AZD1446 was well tolerated, but did not significantly improve ADHD symptoms after 2 weeks of treatment compared to placebo. While the present study does not support the therapeutic utility of AZD1446 in ADHD, its potential pro-cognitive effects remain to be explored in other neuropsychiatric disorders.

A common cause of neuropsychological impairment in older adults is cerebral small vessel disease (SVD), but little is known as to whether lack of awareness of neuropsychological impairment is a feature of this clinical condition. In this study, we investigated awareness deficits in a well-phenotyped population of patients with SVD (n= 45; 21 with defined concomitant neuropsychological impairment) and made comparisons with 24 Alzheimer's disease (AD) patients and a further 80 control participants. Awareness of performance on a range of neuropsychological measures was examined based on the Brief Memory and Executive Test Battery (BMET) (Brookes, Hannesdottir, Lawrence, Morris, & Markus, 2012), exploring the relationship between awareness and memory and executive function. The results revealed significant awareness deficits in both the SVD and AD groups. When splitting the SVD group into those with or without concomitant neuropsychological impairment, only those with neuropsychological impairment showed reduced awareness. For the SVD group, executive function was significantly correlated with awareness but memory was not. By comparison, memory was significantly correlated with awareness in the AD group, with executive function showing a trend but remaining non-significant. The results show that lack of awareness of deficit is a clinical feature of SVD and indicate that there are distinct neuropsychological associations with awareness deficit for SVD and AD.

Background: cerebral small vessel disease (SVD) is the most common cause of vascular cognitive impairment (VCI). Despite this, there is a paucity of rapid simple screening tools to identify cognitive impairment in SVD and differentiate it from other common dementia types. Objective: to validate a new screening test for cognitive impairment in SVD, the Brief Memory and Executive Test (BMET) battery, and examine its ability to detect SVD and differentiate it from Alzheimer's disease (AD). Subjects: 45 patients with SVD, 27 patients with AD and 80 normal controls. Methods: the BMET includes brief tests of executive functioning and processing speed, with comparative tests of memory and orientation. Group discrimination was calculated using discriminant function analysis. Results: the BMET took an average of 10 min to administer. It showed high sensitivity (91%) and specificity (85%) in differentiating SVD patients with cognitive impairment from AD patients. As a comparison the mini-mental state examination had lower sensitivity (63%) and specificity (62%). Conclusions: the BMET is a simple and quick to administer clinical tool for the detection of VCI in SVD and its differentiation from AD impairment. Further multicentre studies are required to evaluate and compare it with other existing screening tests.

Dementia is a complex and often debilitating illness, presenting with not only wide-ranging cognitive impairment but also neuropsychiatric challenges, which can have diverse consequences in quality of life for both patient and caregiver.Studying the validity and reliability of an Icelandic translation of the Neuropsychiatric Inventory with Caregiver Distress (NPI-D).NPI-D was administered to 38 primary caregivers of dementia patients. The concurrent validity was explored by statistically comparing the NPI-D to the Behavioural Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD) and the Geriatric Depression Scale (GDS). Regarding caregiver distress, concurrent validity was established between NPI-D, BEHAVE-AD Global Rating and two other caregiver distress scales.Significant correlation was found when total score on the BEHAVE-AD was compared with total score on the NPI-D. All NPI-D subscales achieved significant correlation with the corresponding BEHAVE-AD subscales apart from the 'depression/dysphoria subscale'. This NPI-D subscale correlated however, significantly with the GDS depression scale, a frequent and well validated measure of depressive symptoms in the elderly population. Cronbach's alpha coefficient indicated a high degree of overall internal consistency among the items of the NPI-D. Interestingly, apathy was the most frequent neuropsychiatric disturbance and the only subscale that differed significantly between dementia severity levels. Finally, when studying caregiver distress, the NPI-D showed good concurrent validity with other measures of caregiver burden and distress.The results demonstrate an acceptable level of validity and reliability; therefore the Icelandic translation of the NPI-D is well suited for identifying neuropsychiatric symptoms in dementia and associated caregiver burden.

In this review, we examine the role of emotion regulation in the treatment of children with anxiety disorders. Cognitive-behavioral therapy (CBT) has been shown to "work" for children with anxiety disorders and it has been categorized as an evidence-based treatment. However, most studies have shown that the treatment is effective for about 60-70% of children, leaving the remaining children symptomatic and oftentimes with persisting psychological disorders. Of importance, it has also been shown that many children with anxiety disorders demonstrate poor emotion regulation skills. Despite these findings, little attention has been directed toward incorporating emotion regulation strategies into these relatively effective cognitive-behavioral treatments. It is possible that CBT programs do not work as well for a portion of children because their emotion regulation deficits, if present, are not being targeted sufficiently. In this review, it is suggested that adding an emotion regulation component could increase treatment efficacy. In addition, strategies aimed at improving emotion regulation at the individual level and at the family level are introduced. Details of how improved emotion regulation skills could be beneficial in bringing about change are discussed. Finally, issues of measurement and the clinical implications for research and practice are considered.

The purpose of this study was to investigate the factors that differentiate best between alcoholic patients who kept their one-year follow-up research appointment and those who did not. Patients attending hospital for alcohol detoxification treatment in Reykjavik were assessed psychologically during the first week of their treatment. One year later they were asked to attend a follow-up appointment for a further psychological evaluation. A total of 313 patients were assessed, 70% were male and 30% were female. Eighty-three (27%) of the patients attended the follow-up appointment. Those who failed to keep their follow-up appointment were significantly younger than the other patients, were more disordered in their personality, had higher trait anxiety, and lower social desirability scores. The severity of their alcohol withdrawal symptoms at the time of treatment was not a significant factor. A discriminant function analysis showed that EPQ Psychoticism was the single best factor that discriminated between the two groups after taking into account other variables, including the age of participants and social desirability.

People who are experiencing alcohol withdrawal are disadvantaged in terms of their ability to cope with leading questions and interrogative pressure (i.e. interrogative suggestibility). What had not been studied previously was the relationship of the severity of alcohol withdrawal symptoms with suggestibility and compliance. Suggestibility and compliance scores, obtained during the first week of hospital admission, were correlated with the severity of alcohol symptoms measured on a daily basis over a 7‐day period in a group of 393 patients attending treatment for alcohol abuse problems. Separate analyses were performed for the male and female patients. Significant gender differences emerged. Among males, alcohol withdrawal symptoms correlated positively with suggestibility and compliance across days. In contrast, among the females alcohol withdrawal symptoms were not significantly correlated with suggestibility and compliance, but were related to confabulations in memory recall. The findings suggest that ...

This study investigated the effects of alcohol withdrawal on suggestibility and mental state. There were three groups of participants. Group 1 was 127 inpatients admitted to a detoxification centre for alcohol abuse. They were assigned to one of seven batches according to their day of hospital admission. Group 2 was 20 of the inpatients (follow-up patients) reassessed between 7 and 12 months after discharge from the hospital. Group 3 was 27 persons who were attending groups run by Alcoholics Anonymous, who had not been tested before and had not consumed alcohol for at least 4 months. All participants completed measurements of mental state (MMSE), state and trait anxiety (STAI), suggestibility, memory, confabulation (GSS), and compliance (GCS). For Group 1, a significant difference across days emerged only on the MMSE. Cognitive functioning improved steadily over time. Patients withdrawing from alcohol (Group 1) were significantly more suggestible than the two 'control' groups (Groups 2 and 3), were overal...

This study examined the effects of the OutSMARTers program on social skills, self-regulation, and executive functions compared with a Waitlist group and a parent training program.Participants were 41 children with ADHD, aged 8 to 10 years. All groups were assessed with behavioral checklists and neuropsychological measures at baseline and post-treatment. The two treatment groups were reassessed with behavioral checklists after 3 months.Findings revealed decreased ADHD symptoms, improved social skills, and better emotion regulation at post-treatment for the OutSMARTers compared with the Waitlist group on subjective measures. No differences were found on objective tasks or between the OutSMARTers and Parent groups after treatment but both treatment groups showed some improvement. In addition, most of the post-treatment changes were maintained for both groups 3 months later.The results indicate that the OutSMARTers program seems to benefit children with ADHD, but further research and treatment development is needed.

The aim of this study was to investigate the effects of alcohol withdrawal on the accuracy of information obtained during an interview, and in the ability of participants to cope with interrogative pressure. Participants were randomly assigned to one of two groups. Group 1: patients to be tested psychologically on the second or third day of their admission. Group 2: patients who were to be assessed towards the end of their 10-day stay in hospital (i.e. after 6 or more days). The participants were a group of 75 patients admitted as inpatients to a detoxification centre in Iceland. They completed measurements of alcohol withdrawal symptoms, Mini-Mental State, state and trait anxiety, suggestibility, memory, confabulation and compliance. Significant differences emerged, as predicted, with regard to impaired cognitive abilities and heightened anxiety symptoms, but no differences were found for suggestibility, confabulation and compliance. However, a significantly larger Shift score on the Gudjonsson Suggestib...

The aim of the study was to investigate the role of personality factors in crime-related amnesia. It was hypothesised that personality factors, such as introversion and good impulse control, would be associated with increased likelihood of psychogenic amnesia. The subjects were 37 offenders referred for a psychiatric evaluation, 18 of whom claimed partial amnesia for the offence. Their scores on a number of psychological tests were compared with the offenders who did not claim amnesia for the offence. Introversion, good impulse control and blaming the offence on mental factors, were significantly related to the reporting of amnesia for the offence. Over-controlled hostility and the scores on lie scales were not associated with the reporting of amnesia.

Objective To investigate the relationships between executive dysfunction, awareness deficits and perceptions of quality of life (QOL) in patients with cerebral small vessel disease (SVD). Method We tested neuropsychological function with simultaneous measurement of awareness performance in 125 participants. Forty-five were carefully phenotyped patients with SVD, defined as a lacunar stroke with corresponding infarct on neuroimaging; and 80 were age-matched controls, providing a normal comparison for neuropsychological measures. Patients also completed the Stroke-Specific Quality of Life Scale. In patients with SVD, the impact of executive dysfunction on awareness and QOL was examined simultaneously using structural equation modeling. Results A simple regression indicated a positive relationship between awareness and QOL. However, when executive function was added to the model, the results showed strong relationships between executive function and awareness, and executive function and QOL, but no direct relationship between awareness and QOL. Conclusion Our results show that the main neuropsychological symptom associated with SVD, namely, executive dysfunction, may predict both reductions in awareness and QOL. However, there is no direct impact of awareness deficits on QOL in patients with SVD, when executive function is included in the model.

To conduct a psychometric analysis to determine the adequacy of instruments that measure cognition in Alzheimer's disease trials.Both the Alzheimer's Disease Assessment Scale - Cognition (ADAS-Cog) and the Neuropsychological Test Battery (NTB) are validated outcome measures for clinical trials in Alzheimer's disease and are approved also for regulatory purposes. However, it is not clear how comparable they are in measuring cognitive function. In fact, many recent trials in Alzheimer's disease patients have failed and it has been questioned if ADAS-Cog still is a sensitive measure.The present paper examines the psychometric properties of ADAS-Cog and NTB, based on a post hoc analysis of data from a clinical trial (NCT01024660), which was conducted by AstraZeneca, in mild-to-moderate Alzheimer's disease (AD) patients, with a Mini Mental State Examination (MMSE) Total score 16-24. Acceptability, reliability, different types of validity and ability to detect change were assessed using relevant statistical methods. Total scores of both tests, as well as separate domains of both tests, including the Wechsler Memory Scale (WMS), Rey Auditory Verbal Learning Test (RAVLT) and Delis-Kaplan Executive Function System (D-KEFS) Verbal Fluency Condition, were analyzed.Overall, NTB performed well, with acceptable reliability and ability to detect change, while ADAS-Cog had insufficient psychometric properties, including ceiling effects in 8 out of a total of 11 ADAS-Cog items in mild AD patients, as well as low test-retest reliability in some of the items.Based on a direct comparison on the same patient sample, we see advantages of the NTB compared with the ADAS-Cog for the evaluation of cognitive function in the population of mild-to-moderate AD patients. The results suggest that not all of ADAS-Cog items are relevant for both mild and moderate AD population.This validation study demonstrates satisfactory psychometric properties of the NTB, while ADAS-Cog was found to be psychometrically inadequate.

A common cause of neuropsychological impairment in older adults is cerebral small vessel disease (SVD), but little is known as to whether lack of awareness of neuropsychological impairment is a feature of this clinical condition. In this study, we investigated awareness deficits in a well-phenotyped population of patients with SVD (n= 45; 21 with defined concomitant neuropsychological impairment) and made comparisons with 24 Alzheimer's disease (AD) patients and a further 80 control participants. Awareness of performance on a range of neuropsychological measures was examined based on the Brief Memory and Executive Test Battery (BMET) (Brookes, Hannesdottir, Lawrence, Morris,Markus, 2012), exploring the relationship between awareness and memory and executive function. The results revealed significant awareness deficits in both the SVD and AD groups. When splitting the SVD group into those with or without concomitant neuropsychological impairment, only those with neuropsychological impairment showed reduced awareness. For the SVD group, executive function was significantly correlated with awareness but memory was not. By comparison, memory was significantly correlated with awareness in the AD group, with executive function showing a trend but remaining non-significant. The results show that lack of awareness of deficit is a clinical feature of SVD and indicate that there are distinct neuropsychological associations with awareness deficit for SVD and AD.

Introduction Perfusion measurement by arterial spin labeling (ASL) techniques is well suited for pharmaceutical magnetic resonance imaging (phMRI) studies to investigate how drugs change the cerebral perfusion status and further, neuronal activity. Materials and method Twelve healthy normal male volunteers participated in the study which was based on a double blinded design. Six subjects were randomly selected to receive a single oral dose of 20 mg d -amphetamine and six were given placebo. Perfusion measurements by pseudo-continuous ASL (pCASL) technique were repeatedly performed at 10 different time points with a 3T clinical MRI scanner during a 10 hour period after dose together with physiologic data and blood sample collections. The dynamic changes in cerebral perfusion in response to the plasma concentration variations of d -amphetamine were analyzed at voxel-level and for regions of interest. Results Compared to the placebo group a 20% reduction in cerebral blood flow (CBF) was observed in gray matter for the subjects that received d -amphetamine. The most significant reduction of regional CBF (rCBF) was detected in the basal ganglia, frontal region and insular cortex using voxel based analysis. A relation between d -amphetamine exposure and CBF response was found using PK/PD modeling, which predicted on average a 15% decrease of the CBF in gray matter at a plasma concentration of 30 ng/ml. Conclusion In this study we have demonstrated that repeated perfusion measurements by pCASL technique was sufficiently robust to differentiate the neurological response between the groups that received d -amphetamine and placebo. Quantitative and repetitive CBF measurements can be used for PK/PD modeling of CNS drug responses in humans.

immunogens in the culture media, DCs from As immunogens-immunized APP/PS1 transgenic mice showed stronger migration, endocytosis and higherMHC II expression than DCs from unimmunizedmice. Further, short As immunogens decreased the secretion of IL-12/IL-10, IL-6/IL-1s and increased the production of TGF-s by DCs from immunized APP/PS1 transgenic mice, but not those from unimmunized mice. Our data indicated that DCs from APP/PS1 transgenic mice were in low-response state to short As immunogens in vitro. Furthermore, immunization with short As immunogens in vivowaked up this abnormal state.Conclusions:Therefore, it is necessary to take abnormal DCs role into consideration in As immunotherapy.

Introduction Recent findings suggest that obstructive sleep apnea (OSA) is very common and underdiagnosed in the early stages of dementia and Alzheimer’s disease (AD). The objective of this study was to assess the prevalence and nightly variance in OSA in mild AD patients in relation to repeated assessments of cognitive function and neuropsychiatric symptoms. Materials and methods Twenty mild AD patients (mini-mental state examination [MMSE] >20; age 45–80 years), over a time period of four weeks, underwent a home type 3 sleep study including pulse oximetry, assessment of respiratory effort, airflow, body position and movement. CogState computerized cognitive assessments and the psychomotor vigilance test (PVT) were performed each morning following the sleep assessments to measure visual memory, attention/vigilance and working memory. Participants additionally completed the Epworth Sleepiness Scale and the Neuropsychiatric Inventory (NPI) was administered to their caregivers. Results The preliminary results showed an OSA prevalence of 90% (AHIiÝ5) and an average (iASD) AHI of 13.0 (iA5.7) events/hour over 5 assessments (12 patients had mild OSA, 3 moderate and 3 severe OSA). Substantial nightly fluctuations in OSA were seen with an average AHI fluctuation of 13.4 (iA9.9) events/hour. Moreover, patients with an average AHIiÝ10 (n = 10 subjects) performed significantly worse on a test of visual attention/vigilance and presented with more apathy as a neuropsychiatric symptom than patients with an average AHI Conclusion OSA appears be underdiagnosed in AD and repeated assessments may lead to a more accurate diagnosis of OSA due to the nightly fluctuations in OSA severity. Preliminary findings suggest that cognition and neuropsychiatric symptoms in AD patients may be adversely affected by increased severity of OSA. Also, subjective reporting of sleepiness may not be suitable to screen for OSA in AD patients. Further studies are warranted to better understand the effects of OSA and its treatment on the clinical symptomatology of AD. Acknowledgements Grant support from AstraZeneca.

The neuropsychology of anosognosia for memory impairment in Alzheimer's disease (AD) was examined in 92 AD patients and 92 case matched individuals for comparison, using three quantitative methods of assessment: Experimenter Rating Scale (ERS), Objective Judgement Discrepancy (OJD) and Subjective-Rating Discrepancy (SRD). The OJD showed significant domain specific correlations with memory functioning as well as a significant correlation with susceptibility to intrusional errors. Memory or executive dysfunction may affect the immediate ability to judge cognitive performance in a domain specific manner (secondary anosognosia). Longer-term awareness of cognitive deficit appears less influenced by impaired basic cognitive functions, than by the decline of metacognitive function (primary anosognosia).

The Alzheimer's Disease Assessment Scale (ADAS) is designed for screening of cognitive and non-cognitive dysfunctions characteristic of persons with probable Alzheimer's disease (AD). The cognitive part of the scale (ADAS-Cog) is both convenient for screening of probable AD and as a measure of cognitive functioning during drug intervention. The aim of this study was to translate the ADAS-Cognitive sub-test (ADAS-Cog) into Icelandic and to study its application in an elderly Icelandic population. The Mini-Mental State Examination (MMSE) and the ADAS-Cog were administered to 20 AD patients and 20 controls. Each patient was also rated on the Global Deterioration Scale (GDS). The probable AD patients were divided into two groups based on their GDS: 3-4 and 5-6 points. The patients were also divided into two groups based on their MMSE score: very mild to mild (23-30 points) and mild to moderate (15-22 points). Furthermore, the subjects were divided into two age groups: 65-76 and 77-92 years. Results revealed a highly significant difference on MMSE (22.3 +/- 3.4; 26.8 +/- 1.6; P0.05) and ADAS-Cog (18.4 +/- 7.7; 7.3 +/- 3.5; P0.05) scores for patients and controls respectively. AD patients also performed significantly worse than the elderly control group on eight of the 11 sub-tests. Thus, the present findings are mainly in line with those of previous studies. The scale exceeds other screening tests such as the MMSE in that it addresses in more detail the symptoms of AD and is valuable for early detection of the illness and staging. ADAS-Cog plays an important role in the diagnostic makeup of AD along with other detailed investigations, such as neuropsychological assessment.