MLA (ASCP) Practice Questions (2026) — Free Sample Questions with Answers

Answer: C

Gold serum separator tube: Serum tubes come after citrate in the CLSI order; clot activator carried into the citrate tube can affect coagulation results.

Lavender K2 EDTA tube: EDTA is drawn near the end; EDTA carryover into later tubes chelates calcium and falsely raises potassium.

Light-blue citrate tube: Correct. CLSI order: blood cultures, citrate, serum, heparin, EDTA, then fluoride/oxalate.

Gray sodium fluoride tube: Fluoride/oxalate tubes are drawn last because their additives inhibit enzymes and bind calcium.

CLSI order of draw: blood culture → light blue → red/gold → green → lavender → gray. It prevents additive carryover.

Answer: B

Too little blood clots the tube before testing: An underfilled tube has relatively more anticoagulant, not less, so clotting is not the problem.

Excess citrate dilutes and over-anticoagulates the sample: Correct. The 9:1 blood-to-citrate ratio is disturbed, so excess citrate binds calcium in the test system and falsely prolongs clotting times.

The plasma becomes hemolyzed from the vacuum: Hemolysis may occur in difficult draws, but the reason for rejection here is the incorrect ratio.

Platelets clump and falsely shorten clotting times: Platelet clumping is not the main effect of underfilling; prolonged times are expected.

Citrate tubes must be filled to at least about 90% of the fill line to keep the 9:1 ratio; underfilled tubes give falsely prolonged PT/aPTT.

Answer: C

Keep it in a 37 °C water bath until testing: Warming is used for cold agglutinins and cryoglobulins, not bilirubin.

Place it in an ice-water slurry: Chilling is not what protects bilirubin; light exposure is the main problem.

Wrap it in foil or use an amber tube: Correct. Bilirubin breaks down on exposure to light, so the specimen is protected with an amber container or foil.

Leave it uncapped so it can degas: Specimens should stay capped to prevent evaporation and contamination.

Light-sensitive analytes (bilirubin, some vitamins such as A and B6, porphyrins) need amber tubes or foil wrapping.

Answer: D

Release the patient results, since only one control failed: A single control beyond ±3 SD (1-3s rule) signals a likely error; patient results cannot be released.

Repeat the control until it falls within range: Repeating controls until one passes hides real problems.

Change the control's acceptable range to include the value: Altering limits to fit a result defeats QC and is not acceptable.

Hold patient results and notify the testing personnel: Correct. An out-of-control run must be stopped and the technologist or supervisor notified to troubleshoot before results are reported.

A control beyond ±3 SD rejects the run: hold patient results, report to the responsible tester, and document the corrective action.

Answer: D

Squeezing increased red cell glycolysis: Glycolysis happens over time in collected blood; it does not occur in the seconds of a fingerstick.

Squeezing caused falsely high hematocrit: Higher hematocrit can lower some meter readings, but squeezing mainly adds tissue fluid rather than concentrating cells.

Squeezing activated the meter's low-battery mode: The collection technique has no effect on the meter's battery.

Squeezing diluted the blood with tissue fluid: Correct. Milking the finger forces interstitial fluid into the drop, diluting it and giving a falsely low result.

Capillary glucose: warm the site, let alcohol dry, wipe away the first drop, and avoid squeezing hard.

Answer: B

Read within 30 minutes; acceptable range 20–25 °C: Room temperature would suggest a substituted specimen, and 30 minutes is far too late to read.

Read within 4 minutes; acceptable range 32–38 °C: Correct. Under 49 CFR Part 40, temperature is read within 4 minutes of collection and must be 32–38 °C (90–100 °F).

Read within 10 minutes; acceptable range 36–40 °C: Both the timing and the range are incorrect for DOT collections.

Read only if the donor seems suspicious; any range: Temperature is checked on every DOT specimen, not only when tampering is suspected.

DOT urine drug collection: temperature strip read within 4 minutes, 32–38 °C; out of range means a directly observed recollection and documentation on the custody form.