3.5 Point of Care Testing and Laboratory Procedures
Key Takeaways
- CLIA-waived tests are simple laboratory tests that medical assistants can perform with minimal training, including glucose monitoring, urine dipstick, rapid strep, and pregnancy tests
- Quality control (QC) must be performed according to manufacturer instructions, typically with each new lot number, new reagent, and at regular intervals
- Urinalysis includes three components: physical (color, clarity, specific gravity), chemical (dipstick for pH, protein, glucose, blood, etc.), and microscopic (cells, casts, crystals)
- Normal fasting blood glucose is 70-100 mg/dL; A1C below 5.7% is normal; results above these ranges may indicate prediabetes or diabetes
- Specimen labeling must include patient name, date of birth, date and time of collection, collector's initials, and test ordered
- Chain of custody procedures are required for drug screening specimens to ensure legal defensibility of results
Last updated: March 2026
Point of Care Testing and Laboratory Procedures
Point of care testing (POCT) refers to laboratory tests performed at or near the site of patient care, with results available quickly to guide clinical decisions. Medical assistants frequently perform CLIA-waived tests in physician offices and clinics.
CLIA Regulations
The Clinical Laboratory Improvement Amendments (CLIA) regulate all laboratory testing performed on human specimens:
| CLIA Category | Complexity | Who Can Perform | Examples |
|---|---|---|---|
| Waived | Simple, minimal risk of error | Medical assistants, trained staff | Glucose meters, urine dipstick, rapid strep, pregnancy tests |
| Moderate complexity | Requires more training | Medical laboratory technicians | CBC (automated), basic chemistry panels |
| High complexity | Requires specialized training | Medical technologists, pathologists | Flow cytometry, genetic testing |
CLIA-waived tests commonly performed by MAs:
- Blood glucose monitoring (glucometer)
- Urine dipstick analysis
- Urine pregnancy test (hCG)
- Rapid strep test (Group A Streptococcus)
- Rapid influenza test
- Fecal occult blood test (FOBT/iFOBT)
- Hemoglobin A1C (certain devices)
- Prothrombin time/INR (certain devices)
- Rapid COVID-19 antigen test
- Mononucleosis rapid test
Quality Control (QC)
Quality control ensures test results are accurate and reliable:
| QC Component | Purpose | When |
|---|---|---|
| Control samples | Known-value specimens tested to verify instrument accuracy | Each new lot, new reagent, as per manufacturer schedule |
| Calibration | Adjusting the instrument to known standards | Per manufacturer instructions |
| Proficiency testing | External evaluation of lab accuracy | Required for moderate/high complexity labs |
| Temperature logs | Monitoring refrigerator/freezer temperatures for reagent storage | Daily |
| Maintenance logs | Documenting instrument maintenance and calibration | Per schedule |
| QC log | Recording all QC results, actions taken for out-of-range results | With each QC run |
If QC is out of range:
- Do NOT report patient results
- Troubleshoot (check expiration, repeat with new control, recalibrate)
- Repeat QC
- Only report patient results when QC is within acceptable range
- Document all corrective actions
Urinalysis
Three Components of a Complete Urinalysis:
1. Physical Examination:
| Parameter | Normal | Abnormal |
|---|---|---|
| Color | Pale yellow to amber | Red (blood), dark amber (dehydration), cloudy (infection) |
| Clarity | Clear | Cloudy/turbid (bacteria, WBCs, crystals) |
| Specific gravity | 1.005-1.030 | High (dehydration), low (overhydration, kidney issues) |
| Odor | Mild, slightly aromatic | Foul (infection), fruity/sweet (ketones in diabetes) |
2. Chemical Examination (Dipstick):
| Parameter | Normal | Clinical Significance of Abnormal |
|---|---|---|
| pH | 4.5-8.0 (avg 6.0) | Alkaline: UTI; acidic: dehydration, diabetic ketoacidosis |
| Protein | Negative | Positive: kidney disease, preeclampsia |
| Glucose | Negative | Positive: diabetes, renal threshold exceeded |
| Ketones | Negative | Positive: diabetic ketoacidosis, starvation, low-carb diet |
| Blood | Negative | Positive: UTI, kidney stones, menstrual contamination |
| Bilirubin | Negative | Positive: liver disease, bile duct obstruction |
| Urobilinogen | 0.2-1.0 mg/dL | Elevated: liver disease, hemolytic anemia |
| Nitrite | Negative | Positive: bacterial UTI (gram-negative bacteria) |
| Leukocyte esterase | Negative | Positive: WBCs present — possible UTI |
| Specific gravity | 1.005-1.030 | High/low: kidney function, hydration status |
3. Microscopic Examination (performed by provider or qualified technician):
- Red blood cells, white blood cells, epithelial cells
- Bacteria, yeast
- Casts (hyaline, granular, cellular)
- Crystals (uric acid, calcium oxalate)
Blood Glucose Testing
Normal Values:
| Test | Normal | Prediabetes | Diabetes |
|---|---|---|---|
| Fasting blood glucose (FBG) | 70-100 mg/dL | 100-125 mg/dL | ≥126 mg/dL |
| Random blood glucose | <140 mg/dL | — | ≥200 mg/dL (with symptoms) |
| Hemoglobin A1C | <5.7% | 5.7-6.4% | ≥6.5% |
| Oral glucose tolerance test (OGTT) | <140 mg/dL (2-hour) | 140-199 mg/dL | ≥200 mg/dL |
Glucose Monitoring Procedure:
- Verify provider order and patient identity
- Perform hand hygiene; don gloves
- Select the puncture site (fingertip — lateral side is less painful)
- Cleanse with alcohol; allow to air dry completely (alcohol can affect results)
- Puncture with a lancet
- Wipe away the first drop of blood (contains tissue fluid that dilutes the sample)
- Apply the second drop to the test strip
- Record the result and report abnormal values to the provider
Hypoglycemia (<70 mg/dL): Symptoms include shakiness, sweating, confusion, irritability, rapid heartbeat Hyperglycemia (>200 mg/dL): Symptoms include excessive thirst, frequent urination, fatigue, blurred vision
Common Laboratory Tests and Normal Values
| Test | Normal Range | Clinical Significance |
|---|---|---|
| WBC | 4,500-11,000/μL | Elevated: infection, inflammation; Low: immunosuppression |
| RBC | M: 4.7-6.1; F: 4.2-5.4 million/μL | Low: anemia; High: polycythemia |
| Hemoglobin | M: 14-18 g/dL; F: 12-16 g/dL | Low: anemia |
| Hematocrit | M: 42-52%; F: 37-47% | Low: anemia; High: dehydration |
| Platelet count | 150,000-400,000/μL | Low: bleeding risk; High: clotting risk |
| BUN | 7-20 mg/dL | Elevated: kidney dysfunction, dehydration |
| Creatinine | 0.7-1.3 mg/dL | Elevated: kidney dysfunction |
| Total cholesterol | <200 mg/dL | Elevated: cardiovascular risk |
| LDL ("bad") | <100 mg/dL | Elevated: cardiovascular risk |
| HDL ("good") | >40 mg/dL (M); >50 mg/dL (F) | Low: cardiovascular risk |
| Triglycerides | <150 mg/dL | Elevated: cardiovascular risk |
| TSH | 0.4-4.0 mIU/L | High: hypothyroidism; Low: hyperthyroidism |
| PT/INR | PT: 11-13.5 sec; INR: 0.8-1.2 | Monitors warfarin therapy; INR goal typically 2.0-3.0 |
Specimen Collection and Handling
| Specimen | Collection Method | Special Instructions |
|---|---|---|
| Clean-catch urine | Midstream specimen after cleansing | Cleanse perineal area; catch midstream portion |
| 24-hour urine | All urine collected over 24 hours | Discard first void; collect all subsequent; keep refrigerated |
| Stool (FOBT) | Small sample on test card | Avoid red meat, vitamin C, NSAIDs for 3 days before |
| Throat swab | Swab tonsillar area and posterior pharynx | Avoid touching tongue or cheeks; patient should not eat/drink 30 min prior |
| Wound culture | Swab from wound bed | Clean wound first; swab the active border, not the center |
| Sputum | Cough specimen into sterile container | Early morning, deep cough; rinse mouth first |
Specimen Labeling Requirements: All specimens must be labeled with:
- Patient's full name
- Date of birth
- Date and time of collection
- Collector's initials
- Test ordered
- Source/site (if applicable)
Test Your Knowledge
Which of the following is a CLIA-waived test that a medical assistant can perform?
A
B
C
D
Test Your Knowledge
When performing a capillary blood glucose test, why should the medical assistant wipe away the FIRST drop of blood?
A
B
C
D
Test Your Knowledge
A positive result for nitrites AND leukocyte esterase on a urine dipstick most likely indicates:
A
B
C
D