LTP12 key terms

Infection-control practices applied to every patient specimen regardless of known diagnosis, including hand hygiene, gloves, gowns, eye protection, and safe handling of sharps and contaminated waste.

A graded set of containment requirements, from BSL-1 through BSL-4, specifying facility design, equipment, and work practices needed to safely handle organisms of increasing hazard.

Protection of the worker and immediate laboratory environment from infectious agents, achieved through good technique, personal protective equipment, and biological safety cabinets.

A ventilated enclosure that uses directional airflow and HEPA filtration to protect the operator, the sample, or both from aerosols generated during handling of infectious or sterile materials.

Formation of fine airborne droplets or particles from actions such as uncapping tubes, pipetting, centrifuging, or flaming loops, which can carry infectious agents into the breathing zone.

A percutaneous injury from a needle, lancet, blade, or broken glass that can transmit bloodborne pathogens, requiring immediate first aid, reporting, and source evaluation.

A written program describing how a laboratory identifies, prevents, and responds to occupational exposure to bloodborne and other infectious agents, including training and post-exposure follow-up.

A documented set of laboratory-specific policies and procedures for safe use, storage, and disposal of hazardous chemicals, including engineering controls and required training.

A standardized document listing a chemical's hazards, handling precautions, first-aid measures, and spill response, which must be accessible to anyone working with that substance.

A tray, cabinet, or barrier placed beneath chemical or biological containers to capture leaks and spills, preventing spread to the work surface, floor, or drainage system.

Verification that the specimen and its container belong to the correct person, typically using at least two independent identifiers at collection and again before any testing or result release.

Applying accurate, legible identifiers and collection details to a container at the bedside or collection site, enabling traceability from patient to result and preventing misattribution.

A documented, unbroken record of who collected, handled, stored, and transported a specimen, used when legal or forensic defensibility of results is required.

Predefined conditions such as mislabeling, insufficient volume, wrong tube, hemolysis, or delayed transport that require a specimen to be refused or recollected because results would be unreliable.

The prescribed sequence for filling blood collection tubes so that additive carryover between tubes does not contaminate later specimens and invalidate test results.

Transfer of an additive such as EDTA or heparin from one collection tube into the next through the needle, potentially distorting electrolyte or coagulation results.

The interval a constricting band remains on the arm during venipuncture; prolonged application concentrates proteins and cells and alters potassium, lactate, and other analyte values.

An increase in the concentration of large molecules and cells in blood caused by prolonged venous stasis, dehydration, or excessive tourniquet time, falsely elevating some analytes.

Release of intracellular contents from ruptured red cells that falsely raises potassium, lactate dehydrogenase, and other analytes and can also interfere optically with measurement.

The ability of a method to detect small amounts of an analyte, usually expressed as the lowest concentration distinguishable from zero with acceptable precision.

The ability of a method to measure only the intended analyte without interference from structurally similar substances, metabolites, drugs, or matrix components present in the sample.

The lowest analyte concentration that can be reliably distinguished from a blank with a stated probability of error, typically estimated from replicate measurements of low-level samples.

The lowest analyte concentration that can be measured with acceptable precision and bias, defining the lower end of the reportable analytical measurement range.

The span of concentrations over which a method produces results meeting defined accuracy and precision goals without dilution, verified during method validation or verification.

The degree to which measured values remain proportional to true analyte concentration across a range, assessed by testing diluted or spiked samples and evaluating deviation from a straight line.

Establishing, through documented studies, that a new or modified method performs adequately for its intended use, covering accuracy, precision, sensitivity, specificity, and interference.

Confirming that a method already validated elsewhere meets the laboratory's performance claims, typically by checking precision, accuracy, and reportable range with the local system.

A mathematical relationship derived from measuring calibrators of known concentration, used to convert instrument signal into an analyte concentration for unknown samples.

A material of assigned analyte concentration used to establish or adjust the instrument response function, differing from control material because its values define the measurement scale.

A sample with known target values run alongside patient specimens to monitor whether a measuring system remains stable and within established acceptance limits.

A control chart plotting quality control results over time against mean and standard deviation limits, making shifts, trends, and random error visually apparent.

A set of statistical decision criteria, such as 1-3s and 2-2s, applied to control results to decide whether an analytical run should be accepted or rejected.

Imprecision that varies unpredictably in direction and magnitude between replicate measurements, widening the distribution of results without shifting the mean.

A consistent deviation of results from the true value in one direction, caused by calibration bias, reagent problems, or interference, and detectable as a shift in control values.

Periodic blinded challenge with externally supplied samples of unknown value, comparing a laboratory's results with peer groups to demonstrate ongoing analytical competence.

An interlaboratory program that distributes samples for analysis and reports comparative performance, supporting accreditation and identification of systematic problems.

The difference between the average measured value and an accepted reference or true value, reflecting systematic rather than random deviation of a method.

An experiment in which a known amount of analyte is added to a sample matrix and the measured increase is compared with the amount added to estimate bias.

An effect from a substance or condition in the sample, such as a drug, hemoglobin, lipid, or bilirubin, that alters the measured result independently of the analyte concentration.

The central range of results, usually covering 95 percent of a defined healthy reference population, used to interpret whether a patient value is typical or unusual.

A carefully characterized group of apparently healthy individuals whose test results are used to derive reference intervals, matched to the patient population as closely as possible.

Comparison of a current result with a patient's previous value to flag unexpectedly large changes that may indicate specimen mix-up, collection error, or a genuine clinical change.

A result so far outside expected limits that it suggests imminent danger to the patient and requires immediate documented notification of a responsible caregiver.

The review step confirming that a result is analytically valid, consistent with specimen quality and prior data, and appropriate for release before it reaches the medical record.

Rules-based software release of results that pass defined analytical and plausibility checks without manual review, with failures routed to a technologist for individual assessment.

A documented step taken to eliminate the cause of a detected nonconformity so it does not recur, distinguished from immediate remedial correction of the problem itself.

A structured investigation, using tools such as the five whys or cause-and-effect diagrams, that identifies the underlying system failures producing an error rather than blaming an individual.

A failure to meet a specified requirement, whether in testing, documentation, or process performance, which must be recorded, evaluated, and resolved under the quality system.

A mislabeled or miscollected specimen in which the blood in the tube does not belong to the named patient, a serious error usually detected by discrepant repeat or historical results.

Documented evaluation, performed before independent testing and at defined intervals, that staff can correctly perform assigned methods, including sample handling, instrument operation, and result reporting.

A written, approved instruction describing exactly how a task is performed, including materials, steps, acceptance criteria, and documentation, so that execution is consistent across staff.

The system ensuring that only current, approved versions of procedures and forms are in use, with revision history, controlled distribution, and removal of obsolete copies.

The elapsed interval from specimen receipt or order entry to result availability, monitored as a key performance indicator of laboratory service and workflow efficiency.