Can the Expanded Disability Status Scale be assessed by telephone?

Information from patients who are unable to continue their visits to a study centre may be of major importance for the interpretation of results in multiple sclerosis (MS) clinical trials. To validate a questionnaire based on the Expanded Disability Status Scale (EDSS), patients in five different European centres were assessed independently by pairs of trained EDSS raters, first by telephone interview and a few days later by standardized neurological examination. Seventy women and 40 men with an average age of 43.7 years (range 19-74 years) were included in the study. Mean EDSS score at the last visit was 4.5 (0-9). EDSS assessment by telephone was highly correlated with the EDSS determined by physical examination (Pearson's correlation coefficient = 0.95). An intraclass correlation coefficient (ICC) of 94.8% was found for the total sample; 77.6% and 86%, respectively, for patients with EDSS < 4.5 (n = 46) and > 4.5 (n = 64). Kappa values for full agreement were 0.48; for variation by +0.5 steps and +1.0 steps, 0.79 and 0.90, respectively. Best agreement could be found in higher EDSS scores, where assessment by telephone interview might be needed most. The telephone questionnaire is a valid tool to assess EDSS score in cases where the patient is unable to continue visiting a study centre or in long-term follow-up of trial participants.

Test-retest reliability and influence of practice effects on performance in a multi-user computerized psychometric test system for use in clinical pharmacological studies.

Fifty naive drug-free healthy young male or female volunteers performed psychometric tests on 6 sessions with 3- to 4-days intervals, using a new multi-user computerized test system for use in clinical pharmacology. Tests of simple reaction time, complex reaction time, concentration, motor coordination, and short-term memory (word pairs or figures) were performed. Clear practice effects were shown for almost every psychometric variable recorded. The magnitude differed considerably between tests. The magnitude of practice effects was most evident (46.5-55.0%) for the concentration test, the coordination test, and the Vienna reaction test. Intermediate practice effects (20.8-31.0%) were observed with the complex reaction test (percent correct reactions) and both short-term memory tests (test duration). Only small practice effects (5.1-14.3%) were observed with the reaction times of the simple and the complex reaction test, and the percent correct responses in the short-term memory tests. After 3 test sessions, significant further improvements could not be shown for most tests, but for the reaction times in the simple and the complex reaction test this was true from the first or the second test session, respectively. For the concentration test and the coordination test, significant practice effects could be shown even after 5 training sessions. It is recommended to perform at least one training session before the start of clinical pharmacological studies with psychometric testing. Test-retest-reliability, as determined from session 5 to session 6 by Spearman's rank correlation coefficient (R8), was very good (> or = 0.95) for the concentration test (percent correct responses) and the coordination test (mean steering time). Most other variables showed intermediate (0.44-0.68) reliability (reaction times in the simple and complex reaction test, percent correct reactions in the complex reaction test, percent errors in the concentration test, test duration of the short-term memory tests). The percent correct answers, which is the primary variable in both short-term memory tests, had a relatively poor reliability (0.14-0.18).

Effect of educational level, gender and age on the performance in a multi-user computerized psychometric test system for use in clinical pharmacological studies.

197 native, drug-free healthy young volunteers performed psychometric tests on a single occasion, using a new multi-user computerized test system which consists of tests of simple reaction time, complex reaction time, vigilance, concentration, motor coordination, short-term memory (word pairs or figures) and abstract language-free reasoning (2 versions). Normality of distribution of all psychometric variables was checked. For the reasoning tests and the memory tests, internal consistency and parallel test reliability were determined. Cross-correlations between the variables and factor analysis were done to evaluate whether different tests measure different brain functions. Multivariate variance analysis was carried out to test the effect of the independent factors school education, gender and age on the performance in the psychometric tests. Subjects with a lower school education level performed worse in the reasoning tests, the concentration test and the memory tests. Females were slower in the coordination test and made fewer correct solutions in the concentration test. Older subjects performed worse in the reasoning tests and had a longer working time in the memory tests than younger ones. The results show the necessity of psychometric screening of volunteers before recruitment for clinical pharmacological psychometric studies in order to reduce-individual variability.

Standard operating procedure for the registration and computer-supported evaluation of pharmaco-EEG data. 'EEG in Phase I' of the Collegium Internationale Psychiatriae Scalarum (CIPS).

The working team 'EEG in Phase I' of the Collegium Internationale Psychiatriae Scalarum presents a standard operating procedure (SOP) for the registration and computer-supported evaluation of pharmaco-EEG data, which is based on published guidelines. The minimum standard for recording, amplifying and filtering, validation of hardware and software, artifact treatment and fast Fourier analysis is described in a tabulated from and further explained as accompanying comments. The available SOP can be the basis for the working out of laboratory-specific SOPs. Compliance with the SOP guarantees the possibility of citation by the International Pharmaco-EEG Group (IPEG), Association for Methodology and Documentation in Psychiatry (AMDP), and Collegium Internationale Psychiatriae Scalarum (CIPS). Furthermore, an optimal standard is recommended where appropriate, which functions as a guideline.

Responses of visual cortical neurons to curved stimuli and chevrons.

Single cells were recorded in area 17 of anaesthetized and paralyzed cats and their responses to curved stimuli and chevrons compared. Striate cells exhibited three different response patterns. A first group responded optimally to a straight line (i.e. zero curvature) and responded similarly to chevrons and to curved lines. A second group responded to all curvatures and was broadly tuned for the straight line when tested with chevrons. A third group responded only to large curvatures, many (2/3) to both signs of curvature and a number (1/3) to only one sign. Cells in this group responded differently to chevrons and curved lines. Cells in these three classes differed both in length-response curve and in width of orientation tuning. Laminar analysis revealed that the three classes are distributed differently across cortical layers. These data shed new light on the finding of Malpeli and coworkers that orientation is extracted at least twice in a cortical column.

Giant aneurysm arising from the anterior cerebral artery and causing an isolated homonymous hemianopsia.

A case of a giant aneurysm arising from the anterior cerebral artery and producing a left homonymous hemianopsia is presented. The aneurysm caused lateral compression of the posterior part of the optic chiasm. After preoperative dynamic assessment of the circle of Willis by angiography and by electroencephalographic recording during carotid artery compression, the aneurysm was trapped with microclips on the anterior cerebral artery proximal and distal to it. Visual field examination 6 months postoperatively showed complete visual field recovery. This is the first case of homonymous hemianopsia caused by an angiographically proven giant aneurysm of the ACA.