VLE flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Backward design sequence

Start from desired program outcomes, then define acceptable evidence such as assessments, and only then design learning activities and instruction that lead to that evidence.

Measurable objective components

A performance stated with an action verb, the conditions under which it occurs, and a criterion such as accuracy or time limit that allows objective judgment of achievement.

Constructive alignment

The three-way match among intended learning outcomes, teaching and learning activities, and assessment tasks; misalignment among the three weakens the validity of any claim of competence.

Criterion-referenced assessment

Scoring that compares learner performance to a fixed predetermined standard rather than to peers, which is the appropriate model for competency-based laboratory education and certification decisions.

Item discrimination index

Computed as the proportion correct in the upper scoring group minus the proportion correct in the lower group; values of 0.30 or higher are generally considered acceptable.

Formative versus summative

Formative assessment informs learning and teaching without a grade consequence; summative assessment certifies achievement at the end of instruction. The two serve different decisions.

Standard precautions scope

Apply to all blood, body fluids, secretions, excretions, non-intact skin, and mucous membranes regardless of whether infection is suspected or confirmed in the patient.

Formaldehyde exposure limits

The eight-hour time-weighted average limit is 0.75 ppm and the short-term exposure limit is 2 ppm; monitoring, labeling, and spill response are required where formaldehyde is used.

Needlestick immediate actions

Wash the site with soap and water without squeezing or scrubbing, report immediately, and seek HIV postexposure prophylaxis as soon as possible, ideally within hours of exposure.

Anemia by MCV

Microcytic anemia is below 80 fL, normocytic is 80 to 100 fL, and macrocytic exceeds 100 fL; the red cell distribution width helps confirm accompanying anisocytosis.

Corrected reticulocyte count

Multiply the reticulocyte percentage by the patient hematocrit divided by the normal hematocrit; this adjusts for anemia severity when judging marrow response.

EDTA pseudothrombocytopenia

Platelet clumping caused by EDTA anticoagulant produces a falsely low automated platelet count; repeat in citrate or heparin and examine the stained smear for clumps before reporting.

PT versus aPTT pathways

Prothrombin time evaluates the extrinsic and common pathways including factor VII; activated partial thromboplastin time evaluates the intrinsic and common pathways including factors XII, XI, IX, and VIII.

Beer-Lambert law

Absorbance equals molar absorptivity times path length times concentration; the relationship is linear only within a limited range, so high results require dilution and reanalysis.

Anion gap formula

Sodium minus the sum of chloride and bicarbonate, normally 8 to 12 mmol/L; an elevated gap with metabolic acidosis suggests ketoacidosis, lactic acidosis, renal failure, or toxin.

Urine nitrite and leukocyte esterase

A positive nitrite with positive leukocyte esterase at alkaline pH supports urinary tract infection; nitrite-negative results do not exclude infection by organisms that do not reduce nitrate.

Hyponatremia initial step

Measure serum osmolality first: low indicates true hypo-osmolar hyponatremia, normal suggests pseudohyponatremia from hyperlipidemia or hyperproteinemia, and high suggests hyperglycemia or mannitol.

Gram stain mechanism

Thick peptidoglycan retains the crystal violet-iodine complex after decolorization, giving purple gram-positive cells; the thin layer and outer membrane of gram-negative cells lose it and counterstain pink.

MacConkey agar interpretation

Selective for gram-negative bacilli and differential for lactose fermentation; lactose fermenters produce pink colonies, while non-fermenters remain colorless on the medium.

Coagulase and catalase tests

Coagulase positivity identifies Staphylococcus aureus among staphylococci; the catalase test separates staphylococci, which are positive, from streptococci, which are negative.

Ova and parasite collection

At least three stool specimens collected on separate days are required because parasite shedding is intermittent; preserved specimens retain morphology for later examination.

Westgard 1-3s rule

A single control observation exceeding the mean by three standard deviations is rejected; this violation most often indicates random error rather than a systematic shift.

Westgard 2-2s rule

Two consecutive control observations exceed the same two-standard-deviation limit, indicating systematic error such as a calibration shift, reagent lot change, or deteriorating control material.

Coefficient of variation

Calculated as the standard deviation divided by the mean, multiplied by 100; a lower value indicates better precision of the measurement procedure.

Sigma metric calculation

Sigma equals total allowable error minus bias, divided by coefficient of variation; values of six or higher are world class and values below three require corrective action.

Delta check purpose

Compares a current patient result with that patient's previous result; a difference exceeding a defined threshold prompts review of specimen identity, integrity, or analytic error before reporting.

Spectrophotometer light path

Light travels from source through monochromator or filter, then the cuvette, then the photodetector, and finally the signal processor, which converts transmitted light to absorbance.

Stray light effect

Stray light reaching the detector limits absorbance linearity, typically above 2.0 to 2.5 absorbance units, so results beyond that range are unreliable and require dilution.

Centrifuge balancing rule

Opposing tubes must be matched by mass, not merely by volume; imbalance causes vibration, rotor damage, and possible release of aerosols from broken tubes.

HIPAA minimum necessary

Each use or disclosure of protected health information is limited to the minimum needed for treatment, payment, or operations, except when the patient authorizes broader release.

Informed consent elements

Capacity to decide, disclosure of risks and benefits and alternatives, comprehension of that information, and voluntariness; a signed form alone does not establish valid consent.

SBAR handoff structure

Situation, Background, Assessment, and Recommendation; the recommendation is stated explicitly and the receiver repeats back critical information to close the communication loop.

Critical value read-back

Notify the responsible caregiver within the defined time and document the value, recipient, time, and read-back confirmation; closed-loop communication verifies the message was received accurately.