The Friedewald equation for calculating LDL cholesterol can be skewed by very high triglycerides or LDL levels, and direct LDL-C measurements are more accurate.

“it's worth noting that these are tend to be calculated the actual LDL value is done using the freed wild equation which uses the measured value of HDL and triglycerides to estimate the LDL so there if triglycerides are very high this can skew that off if LDL is very high it can skew it only certain tests actually do direct ldl-c measurements and you'll generally see that tagged is like LDL direct yeah it'll actually say LDL D instead of LDL C right and so if your lipid panel says LDL see it's probably a calculated LDL which is valuable but not as accurate”