They take 179 serums and they measured in them the Lipoproteins by the two more used laboratory methods: Electrophoresis of lipoproteins in acetate cellulose. and by the Friedewald method (precipitation formula) in order to compare them. They obtained smaller averages In the HDL and LDL with the Friedewald method, but the LDL obtained by the formula were greated with a difference between both of 16%. With each method varied not only the type of hiperlipoproteinemia but the average of hiperlipidemics (HLPC) and normolipidemics (NLPC). The 92.2% of serums are HLPC by the Friedewald method, while the 50.8% of them are HLPC with electrophoresis. The more frecuent type by precipitation formula was the lla (93.3%) and by electrophoresis the type IV (59.3%).