| FXIII | Factor 13, Qual w/reflex to Factor 13 1:1 Mix | — |
| F2A | Factor II Assay (Activity) | — |
| F2IP | Factor II Inhibitor | — |
| F9AG | Factor IX Antigen | — |
| F9A | Factor IX Assay (Activity) | — |
| F9IP | Factor IX Inhibitor | — |
| F5I | Factor V (5) Inhibitor | — |
| LEYDN | Factor V Leiden Mutation | — |
| FVACT | Factor V, Activity | — |
| FVR2DNA | Factor V, R2 Mutation DNA Analysis | — |
| F7I | Factor VII (7) Inhibitor | — |
| FVAC | Factor VII, Activity | — |
| F8AG | Factor VIII Antigen | — |
| F8 | Factor VIII Assay (Activity) | — |
| F8IB | Factor VIII Inhibitor | — |
| FXAC | Factor X Assay (Activity) | — |
| F10CHR | Factor X Chromogenic | — |
| FAXI | Factor XI Assay (Activity) | — |
| F12A | Factor XII Assay (Activity) | — |
| FHPAN | Familial Hypercholesterolemia Panel, Sequencing | — |
| MEFVS | Familial Mediterranean Fever (MEFV) Sequencing | — |
| TTRAS | Familial Transthyretin Amyloidosis (TTR) Sequencing | — |
| FADA | Fanconi Anemia, Group C (FANCC) 2 Mutations | — |
| FAPCP | Fatty Acid Profile, Comp (C8-C26) | — |
| ESSFA | Fatty Acid Profile, Essential | — |
| FAPS | Fatty Acid Profile, Peroxisomal (C22-C26) | — |
| FFACD | Fatty Acids, Free | — |
| FEBAB | Febrile Antibody Panel | — |
| FBLD3 | Fecal Blood, Three Specimens | — |
| FNAKCL | Fecal Electrolytes, 24 hr. or Random | — |
| FF24 | Fecal Fat, 24 Hour | — |
| FATS | Fecal Fat, Random | — |
| SFF | Fecal Fat, Semi-Quantitative | — |
| FBLD | Fecal Occult Blood | — |
| FOBT | Fecal Occult Blood, Colorectal Cancer Screen, Qualitative | — |
| FRED | Fecal Reducing Substances | — |
| FELB | Felbamate | — |
| CDFENT | Fentanyl & Metabolite, UR, Quant | — |
| FENTU | Fentanyl and Analogues, Urine | — |
| FNTLM | Fentanyl and Metabolite, Serum | — |
| FMUQ | Fentanyl and Metabolite, Urine, Quantitative | — |
| FENURQ | Fentanyl, Urine Screen w/reflex to Quant | — |
| FERI | Ferritin | Electrochemiluminescence Immunoassay |
| FIBRN | Fetal Fibronectin | — |
| KLBT | Fetal Hgb Stain (Kleihauer-Betke) | — |
| FIB4R | FIB-4 w/reflex to NASH FibroSure® Plus | Please see individual components for methodology |
| U3RNP | Fibrillarin (U3 RNP) Antibody, IgG | — |
| FDPP | Fibrin Degradation Products, Plasma | — |
| FIBRR | Fibrinogen | — |
| FBRA | Fibrinogen Antigen | — |
| FIBRO | FibroTest-ActiTest, Serum | — |
| FANEU | FISH-Aneuploidy Assay (13,18,21,X,Y) Varies | — |
| FLEC | Flecainide Level, (Tambocor) | — |
| FLOW | Flow Cytometry (Cell Surf Mark) | — |
| FLUCON | Fluconazole, Quantitative | — |
| FLUN | Flunitrazepam and Metabolites (Rohypnol) | — |
| FLUNU | Flunitrazepam and Metabolites (Rohypnol), Urine | — |
| FTACSF | Fluorescent Treponema Antibody, CSF | — |
| FL | Fluoride Quantitative | — |
| FROC | Fluoroquinolone-Resistant Organism, Culture | — |
| FLUO | Fluoxetine (Prozac) | — |
| FLUP | Fluphenazine (Prolixin) | — |
| LUVX | Fluvoxamine (Luvox) | — |
| FOL | Folate, Serum | Electrochemiluminescence Immunoassay |
| AFCOMP | Food Allergens Comprehensive Profile 1 | — |
| FRGX | Fragile X by PCR | — |
| TULAR | Francisella tularensis Abs, IgG and IgM | — |
| FE2 | Free Estradiol by ED/LC-MS/MS | — |
| HGFP | Free Hemoglobin, Plasma | — |
| FKLU | Free Kappa/Lambda Light Chain, Quant, Urine | — |
| FT3E | Free T3 | Electrochemiluminescence Immunoassay |
| FT4MS | Free T4, Equilibrium Dialysis/Mass Spectrometry | — |
| THYL | Free Thyroxine Index Panel | — |
| FRU | Fructosamine | — |
| FSHS | FSH | Electrochemiluminescence Immunoassay |
| FTA | FTA ABS IgG | — |
| FABQ | Fungal Antibodies | — |
| FUNBL | Fungal Culture, Blood | — |
| FUNID | Fungal ID | — |
| KOHP | Fungal Stain-KOH w/Calcofluor White | — |
| FUNGTL | Fungitell (1,3 Beta D Glucan) | — |
| FUNCU | Fungus Culture | — |
| FUNDCU | Fungus Culture, Hair/Skin/Nails | — |
| LSIX | Furosemide (Lasix), Quantitative | — |
