The Boston Naming Test in Swedish: normative data

The purpose of the present study was to introduce a Swedish version of the Boston Naming Test and to offer normative data based on a sample of native Swedish-speaking healthy adults stratified concerning age, gender, and length of education. The subjects were assessed with other lexical tests and half of the group also performed tests of global cognitive function. A semantic analysis of the responses was performed and the typical Swedish naming of the pictures of BNT was investigated. The results showed that long education, high performance on tests of global cognitive ability (FSIQ), verbal fluency, and other lexical tests had a significant positive association to a good performance on BNT whereas age and gender had a minor influence. The response analysis showed that the more difficult an item was, the more variations in the response pattern. To conclude, the Boston Naming Test is appropriate for use in a Swedish-speaking context and an effective test for assessment of naming ability.     

Children's word fluency strategies

Two word fluency tasks, the FAS letter fluency task and the "animal" semantic fluency task, were administered to 130 healthy Swedish-speaking children between 6 and 15 years of age. The main aim was to gather normative data on these word fluency tasks for Swedish-speaking children. Another purpose was to examine the switching and clustering strategies used, along with the occurrence of erroneous responses, in relation to demographic data and number of words retrieved. Both phonological and semantic analyses of switching and clustering were conducted. Higher age was found to be related to a more effective use of phonological and semantic switching and clustering strategies. The reference data resulting from this study may be of clinical value in examinations of children with various diagnoses, including language impairment.     

Swedish norms for word fluency tests: FAS, animals and verbs

Verbal fluency tests are useful measures of acquired language impairment and cognitive decline of various etiologies. The aim of this study was to provide normative data for the Swedish population on the three verbal fluency tests, FAS, Animals and Verbs. A group of 165 healthy participants ranging from 16 to 89 years of age were assessed with the verbal fluency tests and tests of level of intellectual functioning. The sample was stratified by education, age and gender. Level of education had a substantial influence on the performance on verbal fluency, most clearly so in FAS and Verbs. Intellectual level had a positive and significant correlation with all measures of word fluency. Moreover, there was an interaction between age and gender such that women aged between 30 and 64 years outperformed elderly men on FAS and Verbs. Guidelines for instructions and scoring in Swedish are given in the article.     

Reading words with irregular decoding rules: A test of premorbid cognitive function?

The present study investigated the relation between level of general cognitive function and the oral reading of irregular words in Swedish. Swedish is an orthographically regular language, so many irregular words are loan words from other languages. A test comprising such words (irregularly spelled words (ISW)) was designed, and tested on a sample of 48 healthy Swedish adults, stratified according to age, gender, and level of education. The results confirmed that the ability to read words that do not follow the regular rules for decoding in Swedish was positively related to general cognitive level. ISW in combination with demographic variables gave a good estimate of general cognitive function and a better estimate than demographic variables alone. Exposure to written and spoken vocabulary during the lifespan may be indexed by ISW performance, for factor analysis suggested that this may constitute a discrete factor contributing to cognitive function.     

Investigating medical decision‐making capacity in patients with cognitive impairment using a protocol based on linguistic features

A critical question is whether cognitively impaired patients have the competence for autonomous decisions regarding participation in clinical trials. The present study aimed to investigate medical decision‐making capacity by use of a Swedish linguistic instrument for medical decision‐making (LIMD) in hypothetical clinical trials in patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). Three comparable groups (age, education) participated in the study: AD (n = 20; MMSE: 24.1 ± 3.3) and MCI (n = 22; MMSE: 26.7 ± 2.4) patients and healthy controls (n = 37; MMSE: 29.1 ± 1.0). Medical decision‐making capacity was operationalized as answers to questions regarding participation in three hypothetical clinical trials. Answers were scored regarding comprehension, evaluation and intelligibility of decisions, and a total LIMD score was used as the measure of medical decision‐making ability. Groups differed significantly in LIMD with AD patients performing worst and MCI poorer than the control group. A strong association was found between all LIMD scores and diagnosis which supported the assertion that LIMD as it is designed is a one‐dimensional instrument of medical decision‐making capacity (MDMC). The results indicate that a fundamental communicative ability has an impact on the competence for autonomous decisions in cognitive impairment.     

Do adapted vignettes improve medical decision‐making capacity for individuals with Alzheimer's disease?

Medical decision‐making capacity (MDC) is known to decline in individuals with Alzheimer's disease (AD). The vignette method uses hypothetical information as a prerequisite for measuring the capacity to make well‐informed decisions to clinical trials. Our aim was to investigate if adapted vignettes can help individuals with mild AD to assimilate information, make decisions and express them in an understandable way, compared to corresponding decisions based on linguistically more demanding vignettes, as measured by the Swedish Linguistic Instrument for Medical Decision‐making (LIMD). Two vignettes from LIMD were altered linguistically with the aim to facilitate understanding for individuals with AD. An experimental within‐subject design was used to study the influence on MDC of readability (original/adapted vignettes) and content (two different clinical trials). We included 24 patients with mild AD in this prospective study, which read all four vignettes along with a few other tests. This allowed us to investigate the association between MDC and cognitive function. Adapted vignettes did not yield significant differences regarding MDC as compared with original vignettes using a two‐way repeated measures analysis of variance. A difference was found between the two clinical trials where LIMD score was significantly higher for Kidney disease than hypertension vignettes. Our results indicate that adapted vignettes may not improve MDC for individuals with mild AD. MDC was affected by which clinical trial the vignettes regarded, which implies that other factors affecting MDC need to be investigated, like length of text and vocabulary used.     

Estimation of premorbid cognitive function based on word knowledge: the Swedish Lexical Decision Test (SLDT)

In clinical neuropsychology, the present status of a patient is evaluated in relation to the assumed premorbid status. However, in Sweden, existing methods to assess premorbid status are far from optimal. In the present study, the design and evaluation of a Swedish Lexical Decision Test (SLDT) for premorbid global cognitive function (i.e., premorbid intelligence) is described. The design was based on the empirical finding that, in general adult population, word knowledge is strongly associated with measures of global cognitive functioning. Linear stepwise regression analysis demonstrated that SLDT findings accounted for 48% of the variance of global cognitive function as assessed by the Full Scale Intelligence Quotient (FSIQ) from the Wechsler Adult Intelligence Scale Revised (WAIS-R). Demographic variables alone accounted for 31% and a combination of SLDT results and demographics accounted for 60%. Psychometric properties are presented using data from 109 healthy individuals stratified according to age, gender, and level of education. In addition, a case of Alzheimer's disease is presented to illustrate the relationship between SLDT performance and cognitive function. Finally, the theoretical foundation for the relationship between word knowledge and global cognitive function is discussed.