Quantitative clinical neurological testing--II : Some statistical considerations of a battery of tests

A battery of clinical neurological tests was evaluated statistically. In one experiment eight medical students were studied to obtain information on the reproducibility of four observers, eight repeated examinations, and four time periods of day. To obtain learning and fatigue effects another experiment using ten medical students was carried out. The results from this study for these particular groups indicate: 1. 1. That different examiners, such as neurologists and physical therapists, may be trained to obtain comparable results using the quantitative tests of the battery of clinical neurological tests.2. 2. That the level of neurological function obtained using these neurological tests does not vary significantly during the four stated periods of the day.3. 3. That the level of neurological function does not differ significantly when the battery of neurological tests was administered on four consecutive days.4. 4. It is doubtful that a significant learning trend exists when these neurological tests are administered on four consecutive days.5. 5. That the weekly means of most of the neurological tests which involve many repetitions of the same action at each examination are significantly larger for the second week.6. 6. The neurological tests of five repeated trials, e.g., gap strength, and the tests of four reduced trials, e.g., speed of hand, may be used as useful measures of two types of fatigue.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32043/1/0000086.pd

An assessment of the reliability of three methods used in evaluating the status of multiple sclerosis patients

The reliability of three different evaluation methods used in a cooperative clinical trial of the efficacy of ACTH in multiple sclerosis patients was evaluated in a uniformity study that used an efficient statistical design requiring only 10 patients and 5 examiners. The methods were the standard neurologic examination, a scoring system for functional grades and disability status, and a 7-day symptom score. Each patient was examined only 3 times at the beginning of the study and 3 more times 6 days later. No significant differences among the 5 examiners were observed on 82 of the 87 items used to measure neurologic function. With the exception of 1 variable, there were no significant differences among the average values of the sequence of the 3 examinations, nor among the average increments of change in the numerical scores between the first and second trials.In an additional examination in which all 5 examiners simultaneously evaluated 3 patients 1 at a time, it was found that the 5 examiners observed uniformly in all of the neurologic tests.The results of this study indicate that, by and large, the three evaluation methods appear to be reliable in the evaluation of neurologic status when used in a cooperative clinical trial where several investigators contribute data. Furthermore, investigations of reliability in cooperative studies can be performed with the use of efficient statistical designs such as the incomplete Latin-square design.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32998/1/0000382.pd

The importance of age effects on performance in the assessment of clinical trials

Forty young adult normal subjects, 10 Parkinson's disease patients and their 10 matched normal subjects, and 10 multiple sclerosis patients and their 10 matched normal subjects were evaluated in the Quantitative Examination of Neurological Function to determine age effects and the importance of selecting closely matched normal control groups for assessing the performance of patients. Where there are significant differences among the three normal subject groups, it is the oldest normal subject group that differs from the two younger subject groups. Significant decreases in performance with increasing age were found for the steadiness tests performed in the supported position, the sensation tests, two or five tests in the Neuro-Psychological Examination and tests requiring fine skilled movements primarily with the dominant hand. It was found that older subjects made fewer errors in coordinated tasks.A normalization technique, expressing performance as a percentage of normal function, was introduced. A method was developed to provide quantitative and meaningful indices of neurological function. The measure is obtained by averaging the percentage of normal function scores over several tests that belong to a primary category of neurological function.Young adult normal subjects do not perform significantly better than normal subjects in the age range of multiple sclerosis patients; however, young adult normal subjects do perform significantly better than normal subjects in the age range of Parkinson's disease patients, especially on tasks requiring fine skilled movements of the dominant hand and coordinated activities of the lower extremities. These results indicate that the performance of multiple sclerosis patients can be expressed as a percentage of the function of either age-matched normal controls or young adult normal controls. However, the performance of Parkinson's disease patients should be expressed only as a percentage of the function of age-matched normal controls.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33791/1/0000046.pd