Standard deviation (SD) and standard error (SE) are quietly but extensively used in biomedical publications. These terms and notations are used as descriptive statistics (summarizing numerical data), and they are used as inferential statistics (estimating population parameters from samples). I review the use and misuse of SD and SE in several authoritative medical journals and make suggestions ...

OBJECTIVE to evaluate students' learning in an online course on basic life support with immediate feedback devices, during a simulation of care during cardiorespiratory arrest. METHOD a quasi-experimental study, using a before-and-after design. An online course on basic life support was developed and administered to participants, as an educational intervention. Theoretical learning was evalua...

Although cemented all polyethylene (PE) cups have been routinely used in total hip arthroplasty for decades, no computer-assisted method for measurement of radiographic wear has ever been specifically validated for these implants. Using a validated hip phantom model, AP plain hip radiographs were obtained consecutively for eight simulated wear positions. A version of Martell's Hip Analysis Suit...

A recent Perspective in Nature issued a call for more transparency in the reporting of preclinical research (1). Although this article focused primarily on experimental design, it emphasized the need for improved reporting in the scientific literature. Within the context of preclinical studies, there have been discussions regarding the appropriate reporting of standard error (SE) and standard d...

This approach is the standard one when one uses parametric compartmental pharmacokinetic (PK) models. The usual parameter values are either the mean or median as the descriptor of the central tendency, and the standard deviation (SD) as the measure of dispersion. The usual distribution is the common Gaussian bell-shaped curve. Usually the mean is the central value used, and the distribution is ...

In the study of the conformational behavior of complex systems, such as proteins, several related statistical measures are commonly used to compare two different potential energy functions. Among them, the Pearson's correlation coefficient r has no units and allows only semiquantitative statements to be made. Those that do have units of energy and whose value may be compared to a physically rel...