An extensive neuropsychological investigation will be administered in all patients six weeks and 1 year after the index event (using parallel versions for some tests that are susceptible to test-retest effects). Controls will be assessed only once at baseline.
The cognitive assessment includes tests used in other large scale epidemiologic studies covering the main cognitive domains [
33,
34]. Table
2 shows an overview of all cognitive tests performed. Global cognitive functioning will be assessed by the Mini Mental State Examination [
35]. Episodic memory will be measured using the 3-trial version of the Rey Auditory Verbal Learning Test [
36], which includes a delayed recall and a delayed recognition trial, assessing the acquisition and retention of new verbal information. To assess speed of information processing, Parts I and II of the Stroop Color Word test [
37] and the Letter-Digit Substitution Task (an adaptation of the Digit-Symbol Substitution Test [
38]) will be used. Visuoconstructive ability will be assessed by the copy trial of the Rey Complex Figure Test [
39]. With respect to executive functioning, verbal fluency (animal naming, 60 sec) will be used to test response regeneration, the Brixton Spatial Addition Task [
40] will be administered as a measure of concept shifting and rule detection, and the Stroop Interference Score [
32] will be included as a measure of response inhibition. Furthermore participants will complete the Star Cancellation of the Behavioral Inattention Test, a short screening battery to assess the presence of a visual neglect [
41]. Participants will be tested for language deficits by means of the short version of the Token Test, validated for the Dutch language [
42]. To evaluate attention and working memory we will assess the Digit Span subtest from the Wechsler Adult Intelligence Scale - Fourt Edition [
43] and the Paper and Pencil Memory Scanning Task (4 subtasks) [
44]. Subjective cognitive complaints will be assessed by the Cognitive Failure Questionnaire [
45]. The cognitive assessment will be performed in quiet rooms and administered by trained investigators.
Table 2
Neuropsychological assessment
Cognitive assessment |
Global cognitive functioning | Mini mental state examination |
Episodic memory | Rey auditory verbal learning test |
Speed of information processing | Stroop color word test |
| Letter-digit substitution task |
Visuoconstruction | Rey complex figure test - copy |
Executive functioning | Animal fluency test |
| Stroop interference score |
| Brixton spatial anticipation test |
Neglect | Star cancellation |
Language deficits | Short token test |
Attention and working memory | Digit span test |
| Paper and pencil memory scanning task |
Subjective cognitive complaints | Cognitive failures questionnaire |
Mood and functional outcome |
History of depression | |
Anxiety and depression | Mini international neuropsychiatric interview |
Fatigue | Checklist on individual strength (CIS20r) |
Quality of life | EQ-5D |
Health status | Stroke impact scale |
| SF-12 |
Functional outcome | Modified rankin score |
| Barthel index |
| Instrumental activities of daily living |
In addition to the cognitive screening, questionnaires on mood and functional outcome will be administered. Participants will be screened for a history of depressive symptoms with a standardized questionnaire used in previous large-scale epidemiological studies [
47], in which normal reactions to stressful events or normal grief will be excluded. A history of depression is defined as those episodes that require attention of a medical caregiver, including both minor depression and major depressive syndromes as defined by the Research Diagnostic Criteria [
48]. Current anxiety and depression will be evaluated by means of the Mini International Neuropsychiatric Interview [
49], which is a short diagnostic structured interview based on the DSM-IV. Functional outcome will be assessed by mRS, Barthel Index and Instrumental Activities of Daily Living [
50].
Furthermore participants will fill out validated self-report questionnaires on fatigue by means of the Checklist on Individual Strength (CIS20r) [
51] and quality of life by means of the EQ-5D [
52]. Health status will be assessed by means of the Stroke Impact Scale [
53] and SF-12 [
54].