One-Year Reference Norms of Cognitive Change in Spanish Old Adults: Data from the NEURONORMA Sample.

OBJECTIVE: Serial cognitive assessments are useful for many purposes, such as monitoring cognitive decline or evaluating the result of an intervention. In order to determine if an observed change is reliable and meaningful, longitudinal reference data from non-clinical samples are needed. Since neuropsychological outcomes are affected by language and cultural background, cognitive tests should be adapted, and country-based norms collected. The lack of cross-sectional normative data for Spanish population has been partially remediated, but there is still a need of reliable change norms. This paper aims to give an initial response to this need by providing several reliable change indices (RCI) for 1-year follow-up in a Spanish sample. METHOD: A longitudinal observational study was designed. A total of 122 healthy subjects over age 50 were evaluated twice (M = 369.5, SD= 10.7 days) with the NEURONORMA battery. Scores changes were analyzed, and simple discrepancy scores, standard deviation indices, RCI, and standardized regression-based scores were calculated. RESULTS: Significant improvements were observed in variables related to memory, both verbal and visual, visuospatial function, and the completion time of complex problems. Reference tables for several RCI are provided for their use in clinical settings. CONCLUSIONS: Our results confirm the existence of heterogeneous practice effects after 1 year, and support the recommendation of using reliable change norms to avoid misdiagnosis in repeated assessments. This study provides with initial, preliminary norms of cognitive change for its use in Spanish elders. Further studies on larger samples and different inter-visit intervals are still needed.

Cognitive and neuroimaging profiles in mild cognitive impairment and Alzheimer's disease: data from the Spanish Multicenter Normative Studies (NEURONORMA Project).

The aim of this study was to characterize the neuropsychological and neuroimaging profiles of mild cognitive impairment (MCI) and Alzheimer's disease (AD) patients, and to study the magnitude of the differences by comparing both outcomes with healthy subjects in a cross-sectional manner. Five hundred and thirty-five subjects (356 cognitively normal adults (CONT), 79 MCI, and 100 AD) were assessed with the NEURONORMA neuropsychological battery. Thirty CONT, 23 MCI, and 23 AD subjects from this sample were included in the neuroimaging substudy. Patients' raw cognitive scores were converted to age and education-adjusted scaled ones (range 2-18) using co-normed reference values. Medians were plotted to examine the cognitive profile. MRIs were processed by means of FreeSurfer. Effect size indices (Cohen's d) were calculated in order to compare the standardized differences between patients and healthy subjects. Graphically, the observed cognitive profiles for MCI and AD groups produced near to parallel lines. Verbal and visual memories were the most impaired domains in both groups, followed by executive functions and linguistic/semantic ones. The largest effect size between AD and cognitively normal subjects was found for the FCSRT (d = 4.05, AD versus CONT), which doubled the value obtained by the best MRI measure, the right hippocampus (d = 1.65, AD versus CONT). Our results support the notion of a continuum in cognitive profile between MCI and AD. Neuropsychological outcomes, in particular the FCSRT, are better than neuroimaging ones at detecting differences among subjects.

Spanish multicenter normative studies (NEURONORMA project): normative data and equivalence of four BNT short-form versions.

The application of the Boston Naming Test (BNT) is time-consuming and shortened versions need to be developed for screening purposes. The aims of this study were to develop four equivalent 15-item forms of a Spanish adaptation of the BNT, to test the equivalence of the new versions in a clinical sample, and to provide normative data. The normative sample consisted of 340 subjects. The clinical sample included 172 patients (76 Mild Cognitive Impairment and 96 Alzheimer's disease). An empirical procedure was used to develop the shortened versions. All new versions demonstrated satisfactory internal consistency. Pearson's coefficient analysis showed strong relationships among the four short-form versions as well as between each of them and the 60-item test. The inferential confidence interval method demonstrated the equivalence between the four shortened versions. Age and education affected the score of all short-form versions, but sex was found to be unrelated to the performance. Normative data were calculated for midpoint age groups. This paper proposes four 15-item equivalent versions that could be useful and time-saving tools for screening purposes.

Using artificial neural networks in clinical neuropsychology: high performance in mild cognitive impairment and Alzheimer's disease.

Mild cognitive impairment (MCI) is a transitional state between normal aging and Alzheimer disease (AD). Artificial neural networks (ANNs) are computational tools that can provide valuable support to clinical decision making, classification, and prediction of cognitive functioning. The aims of this study were to develop, train, and explore and develop the ability of ANNs to differentiate MCI and AD, and to study the relevant variables in MCI and AD diagnosis. The sample consisted of 346 controls and 79 MCI and 97 AD patients. A linear discriminant analysis (LDA) and ANNs with 12 input neurons (10 subtests of a neuropsychological test, the abbreviated Barcelona Test; age; and education), 4 hidden neurons, and output neuron (diagnosis) were used to classify the patients. The ANNs were superior to LDA in its ability to classify correctly patients (100-98.33% vs. 96.4-80%, respectively) and showed better predictive performance. Semantic fluency, working and episodic memory and education showed up as the most significant and sensitive variables for classification. Our results indicate that ANNs have an excellent capacity to discriminate MCI and AD patients from healthy controls. These findings provide evidence that ANNs can be a useful tool for the analysis of neuropsychological profiles related to clinical syndromes.

Spanish multicenter normative studies (Neuronorma project): norms for the abbreviated Barcelona Test.

The abbreviated Barcelona Test (a-BT) is an instrument widely used in Spain and Latin American countries for general neuropsychological assessment. The purpose of the present study was to provide new norms for the a-BT as part of the Neuronorma project. The sample consisted of 346 healthy controls. Overlapping cell procedure and midpoint techniques were applied to develop the normative data. Age, education, and sex influences were studied. Results indicated that although age and education affected the score on this test, sex did not. Raw scores were transformed to age-adjusted scaled scores (SS(A)) based on percentile ranks. These SS(A) were also converted into age-education scaled scores using a linear regression model. Norms were presented on age-education scaled scores. Also, the a-BT cognitive profile was presented and should prove to be clinically useful for interpretation. These co-normed data will allow clinicians to compare scores from a-BT with all the tests included in the Neuronorma project.

Spanish Multicenter Normative Studies (NEURONORMA Project): norms for the Rey-Osterrieth complex figure (copy and memory), and free and cued selective reminding test.

The Rey-Osterrieth complex figure (ROCF) and the free and cued selective reminding test (FCSRT) are frequently used in clinical practice. The ROCF assesses visual perception, constructional praxis, and visuospatial memory, and the FCSRT assesses verbal learning and memory. As part of the Spanish Normative Studies (NEURONORMA), we provide age- and education-adjusted norms for the ROCF (copy and memory) and for the FCSRT. The sample consists of 332 and 340 participants, respectively, who are cognitively normal, community dwelling, and ranging in age from 50 to 94 years. Tables are provided to convert raw scores to age-adjusted scaled scores. These were further converted into education-adjusted scaled scores by applying regression-based adjustments. Although age and education affected the score of the ROCF and FCSRT, sex was found to be unrelated in this normal sample. The normative data presented here were obtained from the same study sample as all other NEURONORMA norms and the same statistical procedures were applied. These co-normed data will allow clinicians to compare scores from one test with all the tests included in the project.

Spanish Multicenter Normative Studies (NEURONORMA Project): norms for verbal span, visuospatial span, letter and number sequencing, trail making test, and symbol digit modalities test.

As part of the Spanish Multicenter Normative Studies (NEURONORMA project), we provide age- and education-adjusted norms for the following instruments: verbal span (digits), visuospatial span (Corsi's test), letter-number sequencing (WAIS-III), trail making test, and symbol digit modalities test. The sample consists of 354 participants who are cognitively normal, community-dwelling, and age ranging from 50 to 90 years. Tables are provided to convert raw scores to age-adjusted scaled scores. These were further converted into education-adjusted scaled scores by applying regression-based adjustments. The current norms should provide clinically useful data for evaluating elderly Spanish people. These data may be of considerable use for comparisons with other normative studies. Limitations of these normative data are mainly related to the techniques of recruitment and stratification employed.

Spanish Multicenter Normative Studies (NEURONORMA Project): norms for the Stroop color-word interference test and the Tower of London-Drexel.

As part of the NEURONORMA project, we provide age- and education-adjusted norms for the Stroop color-word interference test (SCWT)-Golden version and the Tower of London-Drexel University version (TOL(DX)). The sample consists of 344 and 347 participants, respectively, who are cognitively normal, community dwelling, and ranging in age from 50 to 90 years. Tables are provided to convert raw scores to age-adjusted scaled scores. These were further converted into education-adjusted scaled scores by applying regression-based adjustments. Demographic variables, age, and education significantly affect scores of the SWCT and TOL(DX), sex, however, was found to be unrelated to performance in this sample. The normative data presented here were obtained from the same study sample as all the other NEURONORMA tests. In addition, the same statistical procedures for data analyses were applied. These co-normed data allow clinicians to compare scores from one test with all tests.

Spanish Multicenter Normative Studies (NEURONORMA Project): norms for Boston naming test and token test.

As part of the Spanish Multicenter Normative Studies (NEURONORMA project), we provide age- and education-adjusted norms for the Boston naming test and Token test. The sample consists of 340 and 348 participants, respectively, who are cognitively normal, community-dwelling, and ranging in age from 50 to 94 years. Tables are provided to convert raw scores to age-adjusted scaled scores. These were further converted into education-adjusted scaled scores by applying regression-based adjustments. Age and education affected the score of the both tests, but sex was found to be unrelated to naming and verbal comprehension efficiency. Our norms should provide clinically useful data for evaluating elderly Spaniards. The normative data presented here were obtained from the same study sample as all the other NEURONORMA norms and the same statistical procedures for data analyses were applied. These co-normed data allow clinicians to compare scores from one test with all tests.

Spanish Multicenter Normative Studies (NEURONORMA Project): norms for verbal fluency tests.

Lexical fluency tests are frequently used in clinical practice to assess language and executive function. As part of the Spanish multicenter normative studies (NEURONORMA project), we provide age- and education-adjusted norms for three semantic fluency tasks (animals, fruit and vegetables, and kitchen tools), three formal lexical tasks (words beginning with P, M, and R), and three excluded letter fluency tasks (excluded A, E, and S). The sample consists of 346 participants who are cognitively normal, community dwelling, and ranging in age from 50 to 94 years. Tables are provided to convert raw scores to age-adjusted scaled scores. These were further converted into education-adjusted scaled scores by applying regression-based adjustments. The current norms should provide clinically useful data for evaluating elderly Spanish people. These data may also be of considerable use for comparisons with other international normative studies. Finally, these norms should help improve the interpretation of verbal fluency tasks and allow for greater diagnostic accuracy.

Spanish Multicenter Normative Studies (NEURONORMA Project): norms for the visual object and space perception battery-abbreviated, and judgment of line orientation.

This study forms part of the Spanish Multicenter Normative Studies (NEURONORMA project). Normative data for people aged over 49 years are presented for selected tasks of the visual object and space perception battery (VOSP) and for the judgment of line orientation (JLO) test. Age-adjusted norms were derived from a sample of 341 participants who are cognitively normal and community-dwelling. Age- and education-adjusted norms are also provided. Years of education were modeled on age-scaled scores to derive regression equations that were applied for further demographic adjustments. The normative information provided here should prove useful for characterizing and interpreting individual test performances as well as comparing the scores from these tests with any other test using NEURONORMA norms.

Spanish Multicenter Normative Studies (NEURONORMA Project): methods and sample characteristics.

This paper describes the methods and sample characteristics of a series of Spanish normative studies (The NEURONORMA project). The primary objective of our research was to collect normative and psychometric information on a sample of people aged over 49 years. The normative information was based on a series of selected, but commonly used, neuropsychological tests covering attention, language, visuo-perceptual abilities, constructional tasks, memory, and executive functions. A sample of 356 community dwelling individuals was studied. Demographics, socio-cultural, and medical data were collected. Cognitive normality was validated via informants and a cognitive screening test. Norms were calculated for midpoint age groups. Effects of age, education, and sex were determined. The use of these norms should improve neuropsychological diagnostic accuracy in older Spanish subjects. These data may also be of considerable use for comparisons with other normative studies. Limitations of these normative data are also commented on.