Medical Laboratory Assistant Practice
The Medical Laboratory Assistant Practice domain tests the pre-analytical and defined analytical work that keeps a laboratory functioning: how you receive, prioritize, process, store and test specimens, and how you control and document quality so every result is traceable and defensible. Questions here are situational - they ask what you would do next, not just what a term means.
Working inside the scope of practice
- The MLA collects, processes, loads instruments and performs point-of-care testing under validated procedures; interpreting results and making diagnostic decisions belong to the technologist or pathologist.
- Perform only tasks you are trained, competent and authorized to do. Deviations from a procedure need authorization and documentation.
Specimen workflow and priority
- At receipt, verify two identifiers against the requisition, then check container, volume, temperature and time since collection.
- Accession, then triage: stat and timed specimens first, routine next; notify the requesting area of delays.
- Centrifuge serum tubes only after the clot has formed (commonly 10–15 minutes at room temperature); balance the buckets, cap the tubes, and follow the procedure's speed, time and temperature.
- Label every aliquot with two identifiers, specimen type, date/time and your initials. An unlabeled aliquot is unusable.
- Store per test: serum and plasma at 2–8 °C for short holds, urine refrigerated, light-sensitive analytes wrapped in foil, long-term aliquots frozen at −20 °C or −70 °C as specified.
Quality: QC, QA and calibration
QC is the daily evidence that a test system is performing; QA is the wider system of policies, audits and incident review. Calibration establishes the measurement relationship and does not replace QC. Record lot numbers, expiry dates, control results and corrective action every time a control fails.
Worked example
A point-of-care glucose meter returns a high control outside its acceptable range. Reasoning and action: stop patient testing; repeat the control with a new strip from a new vial; check strip and control expiry and storage conditions; check meter cleanliness and coding; if the control still fails, take the meter out of service, use a backup, notify the supervisor, and document the failure, investigation and corrective action. Patient results from a meter with failed QC are not reportable.
Traps that cost marks
- Reporting patient results after a failed control because "the patient needs it."
- Treating QC and calibration as interchangeable, or assuming waived tests need no QC.
- Partially labeled aliquots or missing initials.
- Ignoring a refrigerator min/max excursion instead of escalating it.
- Centrifuging a serum tube before the clot forms.