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Objective: The present study aimed to investigate the factor structure of a set of neurocognitive tests theoretically assessing executive functions (EF), verbal abilities (VA), and processing speed (PS). This study extended previous research by analyzing if each test is better explained by the specific factor to which it theoretically belongs or by a more general neurocognitive factor; and also by analyzing the relations between the neurocognitive factors., Methods: Using confirmatory factor analysis (CFA) we examined the factor structure of nine neurocognitive tests (EF: Working Memory, Tower, Divided Attention, Stroop, and Verbal Fluency tests; VA: Word List and Confrontation Naming tests; PS: Coding and Telephone Search tests) in a nonclinical sample (N = 90; 18-33 years old, 76 women). We tested five factor models of neurocognitive functioning: a one-factor model; two models with two-correlated factors; and two models with three-correlated factors., Results: A three-correlated-factor model, with EF, VA, and PS factors, was the most suitable for our neuropsychological data. The Verbal Fluency test was better explained by the VA factor rather than by the EF factor. The EF factor was correlated with the PS factor, but not with the VA factor., Conclusions: Most of the neurocognitive measures used in the present study loaded in the expected factors (with the exception of the Verbal Fluency that was apparently more related to VA). EF and PS represent related but separable functions. Our results highlight the need for a careful interpretation of test scores since performance on one test usually requires multiple functions., (© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: This study aimed to investigate the factor structure of the Coimbra Neuropsychological Assessment Battery (BANC), which is an individually administered battery designed to assess a wide range of neurocognitive functions in children., Method: Using the standardization sample of the BANC, a confirmatory factor analysis and a multiple-group analysis were conducted to examine the factor structure and the measurement invariance of three main domains (Memory, Language, and Attention/Executive Functions) in 833 children aged 7-15 years., Results: Consistent with the BANC's conceptualization, the three-correlated-factor model demonstrated the most adequate fit to the data. The measurement invariance of the three-correlated-factor model across two age-groups (7-9 years and 10-15 years) was supported (configural, metric, and partial scalar invariance)., Conclusion: Overall, the BANC shows adequate psychometric properties and provides useful information regarding the children's neuropsychological functioning., (© The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: The Mini-Mental State Examination is the most commonly used cognitive screening test. In Portugal, the cut-off scores are defined according to literacy groups, but different proposals have been recommended by more representative studies. We therefore propose to confirm the influence of demographical variables, such as age and education, in the subjectâs performance; evaluating the discriminant ability of the new normative data; and to further examine the diagnostic acuity of the validated cut-off scoring for mild cognitive impairment and for the most prevalent types of dementia., Material and Methods: Our study includes 1 441 educated subjects, divided into seven subgroups: Mild cognitive impairment, Alzheimer's disease, frontotemporal dementia, vascular dementia, dementia with Lewy bodies, community-controls and memory clinic-controls., Results: Altogether age and education explain 10.4% of the Mini-Mental State Examination results variance, with both variables contributing significantly to the resultsâ prediction. The diagnostic acuity based on the most recent normative data was always higher than the one obtained through the validation cut-off scoring, revealing an overall excellent specificity (superior to 90%) and different sensitivity values: excellent for mild Alzheimer's disease (91%), good for dementia with Lewy Bodies (78%) and low for mild cognitive impairment (65%), frontotemporal dementia and vascular dementia (55%)., Discussion and Conclusions: The performance on the Mini-Mental State Examination is influenced by age and education, supporting the use of normative data that consider those variables. With this approach, the Mini-Mental State Examination could be a sensitive and specific instrument for the Alzheimer's disease screening among all healthcare levels. Nevertheless, its diagnostic acuity is limited in other conditions frequently seen in memory clinics, such as Mild Cognitive Impairment and other types of dementia.

The psychometric properties of the Montreal Cognitive Assessment (MoCA) were examined by using the Partial Credit Model. The study sample included 897 participants who were distributed into two main subgroups: (I) the clinical group (90 patients with Mild Cognitive Impairment, 90 patients with Alzheimer's disease, 33 patients with Frontotemporal Dementia, and 34 patients with Vascular dementia, whose diagnoses were previously established according to a consensus that was reached by a multidisciplinary team, based on the international criteria) and (II) the healthy group (composed of 650 cognitively healthy community dwellers). The results show (i) an overall good fit for both the items and the persons' values, (ii) high variability for the cognitive performance level of the cognitive domains (ranging between 1.90 and -3.35, where "Short-term Memory" was the most difficult item and "Spatial Orientation" was the easiest item) and between the subjects on the scale, (iii) high reliability for the estimation of the persons' values, (iv) good discriminant validity and high diagnostic utility, and (v) a minimal differential item functioning effect related to of pathology, gender, age, and educational level. MoCA and its cognitive domains are suitable measures to use for screening the cognitive status of cognitively healthy subjects and patients with cognitive impairment., (© The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Memory impairment is often present in frontotemporal dementia (FTD) as a result of an inefficient use of learning strategies, sometimes leading to a misdiagnosis of Alzheimer's disease (AD). The Free and Cued Selective Reminding Test (FCSRT) is a memory test that controls attention and acquisition, by providing category cues in the learning process. The main goal of this study was to show the usefulness of the FCSRT in the distinction between behavioral (bv-) FTD and AD. Three matched subgroups of participants were considered: bv-FTD (n = 32), AD (n = 32), and a control group of healthy adults (n = 32). Results proved that while AD patients exhibited an overall impairment in FCSRT, bv-FTD subjects showed to benefit more from the controlled learning through category cues. AD patients were 25 times more likely to have an impaired FCSRT. The FCSRT has shown its utility in the distinction between bv-FTD and AD, therefore increasing the diagnostic accuracy., (© The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The Clock Drawing Test has been systematically used to assess visuospatial deficits related to the parietal lobes, but we now acknowledge its much more complex relation with other cognitive abilities. Despite its common use in clinical and investigational practices, no study has developed normative data for the Portuguese population. We present the distribution of clock drawing scores using three scoring systems in a representative community sample of cognitively healthy subjects. We found that the systems were well correlated with each other and with cognitive screening tests widely used and had good psychometric properties. Normative data for the three scoring systems were developed considering age and education. These results allow a more rigorous interpretation of the test performance in clinical context and are especially relevant for epidemiological research.

The Montreal Cognitive Assessment (MoCA) is a brief cognitive instrument for screening milder forms of cognitive impairment. The present study aimed to analyze the influence of sociodemographic (age, gender, educational level, marital and employment status, geographic region, geographic localization, and residence area) and health variables (subjective memory complaints of the participant and evaluated by the informant, depressive symptoms, and family history of dementia) on the participants' performance on the MoCA. The investigation was carried out in a Portuguese community-based sample of 650 cognitively healthy adults, who were representative of the distribution observed in the Portuguese population. Educational level and age significantly contributed to the prediction of the MoCA scores, explaining 49% of the variance. Regarding health variables, only the subjective memory complaints of the participant showed a small contribution (9%) to the variance on the MoCA scores. This study contributes a useful approach to understanding MoCA performance, stressing the great impact of education and age on scores.

Although patients with Alzheimer disease (AD) share clinical and histological features regardless of age of onset, the hypothesis that early onset AD constitutes a distinct subgroup prevails. Some authors suggest that early attention or language impairment constitute patterns of differentiation in terms of neuropsychological profile, between these groups. However, investigations are not consensual in terms of cognitive domains affected in each group. Aim: To investigate whether there is early neuropsychological difference between two types of AD using the conventional dividing line of 65 years. Methods: We evaluated the results obtained in the Mini-Mental State Examination (MMSE) and in a comprehensive neuropsychological battery - Battery of Lisbon for the Assessment of Dementia (BLAD), at a Dementia clinic in the University Hospital of Coimbra and a Memory Clinic. The study was developed in consecutive patients with a clinical probable diagnosis of mild to moderate AD, using standard criteria (DSMIV and NINCDS-ADRDA). Statistical analysis was performed using Qui-square and U-Mann-Whitney, for categorical and non-categorical variables. The degree of relation between variables, was measured using the coefficient of correlation rs de Spearman. Results: The total sample included 280 patients: 109 with early onset AD and 171 with a late-onset form. Groups were comparable in terms of gender, education or severity of disease, and MMSE. In BLAD, for univariate analysis the early onset group had lower scores in Naming (p = 0.025), Right-Left Orientation (p = 0.029) and Praxis (p = 0.001), and better performances in Orientation (p = 0.001) and Visual Memory (p = 0.022). After application of Bonferroni correction for multiple comparisons only Praxis and Orientation could differentiate the two groups. No significant differences were found in other tests or functions. Discussion: The results are suggestive of dissociated profiles between early and late-onset AD. Younger patients have a major impairment in Praxis and a tendency for a great impairment in neocortical temporal functions. AD patients with late-onset forms had a tendency for worse performances in Visual Memory and Orientation, suggesting a more localized disease to the limbic structures. [ABSTRACT FROM AUTHOR]