tailieunhanh - MEDICAL STATISTICS - PART 2

Một biến chất lượng cuộc sống được sử dụng để đánh giá khả năng của bệnh nhân để thực hiện các hoạt động hàng ngày như cho ăn, tắm rửa, mặc quần áo, vv có thể được sử dụng để xác định một mức độ cơ bản của hoạt động và giám sát cải tiến trong hoạt động hàng ngày | Barthel index A quality-of-life variable used to assess the ability of a patient to perform daily activities such as feeding bathing dressing etc. Can be used to determine a baseline level of functioning and to monitor improvements in activities of daily living over time. A score of zero corresponds to complete dependence on others and a score of ten implies that the patient can perform all usual daily activities without assistance. See also activities of daily living scale and U-shaped distribution. International Disability Study 1988 10 61-3. Bartlett s test A test for the equality of the variances of more than two populations. Very sensitive to non-normality so that a significant result might be interpreted as an indication of the non-equality of the population variances when in reality it is due to the non-normality of the observations. See also Box s test and Hartley s test. Bartlett s test Do not take the results of this test too seriously. Baseline balance A term used to describe in some sense the equality of the observed baseline characteristics among the groups in say a clinical trial. Conventional practice dictates that before proceeding to assess the treatment effects from the clinical outcomes the groups must be shown to be comparable in terms of these baseline measurements and observations usually by carrying out appropriate significant tests. Such tests are criticized frequently by statisticians who usually prefer important prognostic variables to be identified before the trial and then used in an analysis of covariance. Senn S. 1997 Statistical Issues in Drug Development J. Wiley Sons Chichester. Baseline balance Avoid the foolish but common use of baseline measurements to check that the groups in a randomized clinical trial are balanced . Baseline characteristics Observations and measurements collected on subjects or patients at the time of entry into a study before undergoing any treatment for example sex age and weight. Basic reproduction number A