This document describes the PRIMED Harmonization algorithms for HDL-C, LDL-C, and TG.
• High density lipoprotein (HDL-C)
• Triglycerides (TG):
o Non-fasting
• Low-density lipoprotein (LDL-C):
o Unadjusted non-fasting
o Adjusted non-fasting
Overall procedure
1. Extract trait measurements using measurement codes and calculations
2. Convert measurement units to expected units, if necessary
3. Apply measurement exclusion criteria
4. Prepare measurements for analysis
5. After preparing measurements for analysis, remove statistical outliers
6. Compute a single value per individual for inclusion in analysis
7. Calculate counts of flagged individuals
Codes to ascertain HDL-C, LDL-C, and TG are available in individual csv files on this page. All units should be in mmol/L for this harmonization. The detailed algorithm document outlines how to adjust and convert all values based on unit and medication status.
Statistical outliers will be removed after adjustment for medication to remove measurements outside of +/- 6 SD of the overall mean lipid value in the total population. A single value for each individual will be gathered by using the earliest timepoint in the EHR with a record for each value.
Flags should also be listed for all of the following conditions:
• Cushing's Syndrome
• Hypopituitarism
• Hypothyroidism
• Liver cirrhosis
• Nephrotic syndrome
• Polycystic Ovarian Syndrome (PCOS)
• Type 2 Diabetes
