| Test name | Alternative name for |
|---|
| Raltegravir | |
| Raltegravir Resistance Testing | HIV-1 Integrase Inhibitor Susceptibility |
| Random Blood Glucose | Glucose |
| Rapamycin | Sirolimus |
| Red Cell Folate | Folate; Red Cell |
| Red Cell Magnesium | Magnesium Red Cell |
| Red Cell Zinc | Zinc Red Cell |
| Reducing Substances Faeces | Faecal Reducing Substances |
| Reducing Substances Urine | |
| Regulatory T cells | |
| Renal Biopsy | Histology - Renal Biopsy |
| Renal Stone | Calculi Analysis |
| Renin Ambulant | |
| Renin Recumbent | |
| Reptilase Time | |
| Respiratory PCR | |
| Respiratory Synctial Virus Serology | |
| Reticulin autoantibody | Anti Reticulin antibodies |
| Reticulocyte haemoglobin content (CHr) | CHr |
| Reticulocytes | |
| Retinol | Vitamin A |
| Retinol Binding Protein | |
| Rheumatoid Factor | |
| Ri antibodies | Anti Neuronal antibodies |
| Riboflavin | Vitamin B2 |
| Ribosomal P antibodies | Extended ENA Autoantibody Panel Sendaway |
| Ribosomal RNA | 16S rRNA Bacterial Identification |
| Rickettsial Culture | |
| Rickettsial DNA by PCR | |
| Rickettsial Serology | |
| RiCOF | Ristocetin Cofactor |
| Rifabutin | |
| Rifampicin Resistance Mutations (TB) | |
| RIPA (Ristoceitin Induced Platelet Aggregation) | Platelet Aggregation Studies |
| Risperdal | Risperidone |
| Risperidone | |
| Ristocetin Cofactor | |
| Ristocetin Cofactor Inhibition Level Bethesda | |
| Ritonavir | |
| Rivaroxaban | |
| RNA Polymerase III Antibody | |
| RNP | ENA |
| Ro52 | |
| Ross River Virus Serology | |
| Rotavirus EIA | Rotavirus investigation |
| Rotavirus investigation | |
| RP11 | Scleroderma Antibody Line Immunoassay |
| RP155 or TRIM21 (Ro52). | Scleroderma Antibody Line Immunoassay |
| RPOB gene | Rifampicin Resistance Mutations (TB) |
| RPR | Syphilis Serology |
| RSV PCR | Respiratory PCR |
| RSV Serology | Respiratory Synctial Virus Serology |
| Rubella IgM | |
| Rubella Serology | |
| RUNX1-RUNX1T1 Gene Fusion | |