Everyone must wear medical grade gloves in a sterile field. A sterile field is usually used during surgery. A sterile syringe and vial of medication. Surgical hand scrubs remove most bacteria from the skin before gloves are put on.
Standard score. In statistics, the standard score is the signed number of standard deviations by which the value of an observation or data point is above the mean value of what is being observed or measured. Observed values above the mean have positive standard scores, while values below the mean have negative standard scores. The standard score is a dimensionless quantity obtained by subtracting the population mean from an individual raw score and then dividing the difference by the population standard deviation.
Raw score. In statistics and data analysis, a raw score is an original datum that has not been transformed. This may include, for example, the original result obtained by a student on a test (i.e., the number of correctly answered items) as opposed to that score after transformation to a standard score or percentile (%) rank or the like. Often the conversion must be made to a standard score before the data can be used. For example, an open ended survey question will yield raw data that cannot be used for statistical purposes as it is; however a multiple choice question will yield raw data that is either easy to convert to a standard score, or even can be used as it is.