Normative studies of variability in performance by healthy adults on neuropsychological batteries are reviewed. Regarding test score scatter, normative participants often have large discrepancies between best and worst scores. When "abnormality" was defined as a score more than one standard deviation below the mean, in test batteries with at least 20 measures, the great majority of normative pa...

OBJECTIVE To compare (1) the reliability of two expensive and two inexpensive measuring instruments, suitable for use in the community and (2) the reliability of experienced compared with inexperienced observers. DESIGN (1) Ten children aged 5-12 years were each measured three times blindly, and in random order, by two experienced observers using four different portable instruments. (2) Four ...

BACKGROUND In systematic reviews and meta-analysis, researchers often pool the results of the sample mean and standard deviation from a set of similar clinical trials. A number of the trials, however, reported the study using the median, the minimum and maximum values, and/or the first and third quartiles. Hence, in order to combine results, one may have to estimate the sample mean and standard...

Measures of variation are statistical measures which assist in describing the distribution data set. These either used separately or together to give a wide variety ways measuring variability data. Researchers and mathematicians found out that these were not perfect, they violated algebraic laws possessed some weakness could ignore. As result facts, new measure known as geometric was formulated...