Tuesday, September 15, 2015
The Widmark Formula and Factor for the Fit
I've been having trouble getting the Widmark formula and factor to work out properly for Widmark's 1914 data. One can use the intercept of the vertical concentration axis and slope to determine the line which represents the Widmark formula and which in this case is B' = B0 - IBt. The Widmark factor, r, obtained from the B0 = A/(Mr) should be approximately 0.70 but the calculated value is 0.32 instead which is too low. Widmark showed that the concentration of alcohol in urine was approximately the same as that in the blood. So it would appear that the alcohol concentration values for the data are too high.
One can look at the de.wikipedia articles promille, blutalkoholkonzentration, diurese and urin (harn) for more information on the German terminology used in Widmark's paper.