CLIN CHEM

• number of moles of solute per liter (L) of solution

  Molarity
• number of moles of solute per kilogram (kg) of solvent

  Molality
• number of equivalent weights of solute per liter (L) of solution

  Normality
• amount of solute per 100 total units of solution; often expressed as g/100 mL or g/dL

  % w/v
• expression of relative concentration

  Dilution
• volume of sample divided by total volume of solution

  Simple dilution
• amount of something relative to another; usually expressed as part per part

  Ratio
• average or arithmetic mean

  Mean
• midpoint of a data set after the values have been ranked or ordered

  Median
• most frequently occurring value in a data set

  Mode
• Distribution of data points around the mean

  Standard deviation
• the square of SD

  variance
• Most commonly used measure of spread especially when constructing QC chart

  Standard Deviation
• Best indicator of precision


  Coefficient of Variation
• Difference between the highest and lowest values

  Range
• Not usually used since it is greatly affected by the presence of outliers

  Range
• Reference interval: represents the _% confidence limit

  95%
• Data points are distributed symmetrically around the mean (____ curve) with most values close to the center; mean, median, and mode are identical

  bell shaped curve
• _% confidence limit

  95
• Follows the emperical rule

  68-95-99.7%
• 68% of values fall within _ SD

  1 SD
• 95% of values fall within _ SD

  2SD
• 99% of values fall within _ SD

  3SD
• Done to confirm the validity of an existing or published RI for an analyte

  Verifying a reference interval
• Verifying a reference interval requires at least _ study individuals

  20
• When verifying a reference interval, RI is adopted if <_% of the subjects fall outside the range

  10%
• Done when there is no existing RI for an analyte or when transference studies fail

  Establishing a reference interval
• Establishing a reference interval it requires atleast _ study individuals

  120
• when establishing a reference interval, RI is set based on _ 𝒙̅ + 2s

  95%
• First step in method evaluation

  Precision study
• Compare the means of two groups of data or the accuracy of two methods

  t test
• usually done by running two control materials twice a day over a 10-day period

  Precision study
• involves spiking a sample with a known amount of analyte and determining how much of it can be detected by the method in the presence of other compounds in the matrix

  Recovery study
• Compares the standard deviation of two groups of data or the precision of two procedures

  F test
• used to compare two methods using the best fit line through the data points

  Linear Regression
• plotted along the X-axis

  Independent variable/Reference method
• plotted along the Y-axis

  Dependent variable/New method
• ability of a method to detect the smallest concentration of an analyte

  Analytical sensitivity
• ability of a method to detect only the analyte of interest

  Analytical specificity
• ability of a test to detect a given disease or condition

  Diagnostic sensitivity