Lab Data: Interpretation Factors

What is the primary purpose of the color-coding system used for blood collection tubes?

Serum is best described as the liquid component of blood:

For a routine mammalian Complete Blood Count (CBC), which blood collection tube is typically the tube of choice?

Why is it important to avoid filling an EDTA tube before a red top tube when collecting multiple blood samples?

Which of the following is considered a pre-analytical source of error in laboratory testing?

Over- or under-filling a blood collection tube can lead to inaccurate results primarily due to:

In diagnostic testing, sensitivity is defined as the:

What is the potential consequence of using a small vein for blood collection compared to a large vein?

Prolonged draw time during blood collection should be avoided because it can lead to:

Using an incorrect anticoagulant for a specific blood test is an example of which type of error?

If blood is allowed to clot in a tube intended for plasma collection, which component of the blood will be missing or significantly reduced in the resulting sample?

Which color-topped vacutainer tube is specifically designed for coagulation tests?

For glucose determinations, particularly when glycolysis inhibition is required, which vacutainer tube is most appropriate?

Hemolysis, a pre-analytical error, can falsely elevate the results of which of the following analytes?

Lipemia in a blood sample, characterized by turbidity, can interfere with laboratory assays and falsely increase the measurement of:

What is the primary reason for avoiding forcing a blood sample through the needle into a collection tube?

Incompletely filled EDTA tubes can lead to red blood cell crenation due to:

Expired reagents are a source of which type of laboratory error?

What is the role of calibrators in laboratory assays?

Laboratory controls are used primarily to:

Reporting results to the wrong patient is an example of which category of laboratory error?

Why is it emphasized that 'bad data is worse than no data' in the context of laboratory results?

Chemistry results from dehydrated patients may be higher in concentrated plasma due to:

Enzyme activities in a blood sample, measured in U/L, can be affected by:

Reference intervals for laboratory tests are ideally established based on:

Why should each laboratory ideally establish its own reference intervals?

In a box and whisker plot of platelet counts, outliers are identified and should be excluded primarily because they:

If a laboratory has fewer than 20 healthy animals to establish a reference interval, what is the recommended alternative?

A reference interval is designed to reflect approximately what percentage of a healthy population?

A diagnostic cut-off, as an alternative to a reference interval, is primarily established by:

Increased alkaline phosphatase (ALP), calcium (Ca), and phosphorus (Phos) levels might be considered within the reference range for:

A twofold increase in serum potassium (K) is generally considered more clinically significant than a twofold increase in alanine aminotransferase (ALT) because:

It is possible for sick animals to have test results within the reference interval, especially in early stages of disease. For example, a normal creatinine level can be seen in:

Which of the following assay diagnostic properties is most crucial for a screening test?

A diagnostic test with high specificity is best suited for:

If a test has 95% sensitivity, what does this imply regarding false negative results?

In the context of predictive values, disease prevalence significantly affects:

Calculate the accuracy of a diagnostic test given the following values: True Positives (TP) = 6, True Negatives (TN) = 966, False Positives (FP) = 7, False Negatives (FN) = 21.

What is the primary focus of the initial part of the lecture on laboratory tests?

Which category of laboratory errors is most directly controlled by the veterinarian?

If a veterinarian sends a sample to a reference lab, which type of error are they LEAST likely to have direct control over?

What is a potential consequence of using a small vein for blood collection that might NOT occur with a larger vein?

Why is a prolonged blood draw time more likely to cause platelet clumps in a sample?

In blood collection, vacutainers are advantageous in human medicine primarily because they:

Choosing the correct blood collection tube is crucial. What could be a consequence of using the incorrect tube?

Serum differs from plasma primarily due to the:

What is the function of the gel in a serum separator tube (SST)?

Why is it important to allow a red top tube to fully clot before centrifugation?

For which of the following analytes would a red top tube be MOST appropriate?

Why are serum separator tubes (SST) generally NOT recommended for therapeutic drug monitoring, such as phenobarbital levels?

EDTA prevents blood coagulation by:

A chemistry profile result shows a critically low calcium level (e.g., 2 mg/dL) from a sample collected in a purple top tube. What is the MOST likely explanation?

Why is a purple top (EDTA) tube considered a good choice for cell counts?

Lithium heparin is preferred over sodium heparin for general chemistry profiles because:

For 'stat' (immediate) chemistry testing, which anticoagulant tube type is MOST advantageous and why?

In a situation where a very small blood volume is obtained (e.g., from a small animal), which tube type is most versatile if both CBC and chemistry are needed?

Sodium citrate (blue top tubes) is used for coagulation testing because it:

Gray top tubes containing potassium oxalate and sodium fluoride are primarily used for:

If a glucose sample is not processed promptly and is left at room temperature, what is the expected change in glucose levels and why?

How does refrigeration help in preserving glucose levels in a blood sample?

Hemolysis in a blood sample can falsely elevate the results for certain analytes because:

Lipemia, or excessive fat in the blood, can interfere with laboratory assays and falsely increase hemoglobin measurements because:

Forcibly expelling blood from a syringe through the needle into a collection tube can cause:

Underfilling an EDTA tube can lead to red blood cell crenation because:

Expired reagents in a laboratory assay are a source of which type of error?

What is the purpose of calibrating a laboratory instrument when using a new batch of reagents?

Laboratory controls are typically run daily to:

Reporting a patient's lab results under another patient's name is an example of a:

Why are reference intervals laboratory-specific?

In establishing reference intervals, why are outliers typically excluded from the dataset?

If a laboratory has fewer than 20 healthy animals for establishing a reference interval, what is the recommended approach?

A reference interval is statistically designed to include approximately what percentage of a healthy population?

Diagnostic cut-offs, unlike reference intervals, are established primarily to:

Why is a twofold increase in serum potassium generally considered more clinically significant than a twofold increase in alanine aminotransferase (ALT)?

A normal creatinine level in a sick animal might be misleading, particularly in early stages of:

For a disease screening test, which diagnostic property is MOST important?

If a test has 95% sensitivity, what is the implication regarding false negative results?

Disease prevalence in a population significantly affects which diagnostic test property?

Given: True Positives (TP) = 6, True Negatives (TN) = 966, False Positives (FP) = 7, False Negatives (FN) = 21. What is the accuracy of this diagnostic test?

Which category of laboratory errors is most directly influenced by the blood collection process itself?

Veterinarians have the most direct control over minimizing which type of laboratory error?

Using a syringe and needle for blood collection, compared to vacutainers, introduces a slightly increased risk of which pre-analytical error?

The presence of clotting factors is a key distinction when comparing:

What is the primary role of the gel within a serum separator tube (SST)?

Why is it crucial to allow complete clot formation before centrifuging a red top tube?

For which of the following analytes is a red top tube generally considered MOST appropriate for collection?

Serum separator tubes (SSTs) are generally discouraged for therapeutic drug monitoring because:

Ethylene diamine tetraacetic acid (EDTA) prevents blood coagulation by which mechanism?

A critically low calcium result from a purple top (EDTA) tube should raise suspicion of:

Why are purple top (EDTA) tubes considered the preferred choice for performing cell counts?

Lithium heparin is often favored over sodium heparin for general chemistry profiles primarily because:

For 'stat' (immediate) chemistry testing, lithium heparin tubes offer an advantage because:

In situations with very limited blood volume, a green top (heparin) tube is versatile because it allows for:

Sodium citrate (blue top tubes) is specifically used for coagulation testing because it:

If a glucose sample in a plain tube is not promptly processed at room temperature, glucose levels are expected to:

Refrigeration helps preserve glucose levels in blood samples by:

Hemolysis falsely elevates results for certain analytes because:

Lipemia can falsely increase hemoglobin measurements in certain assays due to:

Using expired reagents in a laboratory assay is a source of which type of error?

The primary purpose of calibrating a laboratory instrument with a new batch of reagents is to:

Reporting a patient's laboratory results under a different patient's name is an example of a:

Reference intervals are laboratory-specific primarily because:

In establishing reference intervals, outliers are typically excluded from the dataset because they:

If a laboratory has fewer than 20 healthy animals available for establishing a reference interval, a recommended alternative approach is to:

A reference interval is statistically designed to encompass approximately what percentage of a healthy population?

Diagnostic cut-offs, in contrast to reference intervals, are primarily established to:

A normal creatinine level in a sick animal can be misleading, particularly in the early stages of:

For a disease screening test, which diagnostic property is MOST important to maximize?

If a diagnostic test has a 95% sensitivity, this implies that:

Given: True Positives (TP) = 6, True Negatives (TN) = 966, False Positives (FP) = 7, False Negatives (FN) = 21. Calculate the accuracy of this diagnostic test.

Which of the following scenarios represents a post-analytical error?

An ELISA test for a specific disease can be adjusted to increase sensitivity. What is the MOST likely consequence of increasing the sensitivity of this test?

Consider a scenario where a veterinarian is screening for a rare disease in a general pet population. Which test characteristic is MOST crucial for minimizing missed cases of this rare disease?

In the context of diagnostic testing, what does 'bad data is worse than no data' fundamentally imply?

For which patient condition are chemistry results MOST likely to be falsely elevated due to hemoconcentration?

Enzyme activities in a blood sample, measured in U/L, are MOST susceptible to changes due to:

Reference intervals for laboratory tests are ideally established using samples from:

The primary reason each laboratory should ideally establish its own reference intervals is:

In a box and whisker plot of platelet counts, outliers are identified and should be investigated primarily because they:

When establishing reference intervals, if a laboratory observes platelet clumps on a blood smear associated with unusually low platelet counts, these data points should be:

Which type of laboratory error is LEAST likely to be directly controlled by a veterinarian if samples are sent to a reference lab?

What can occur if a blood sample is collected too slowly using a small-gauge needle?

What is the primary advantage of using vacutainers directly for blood collection, as practiced in human medicine, compared to using a needle and syringe?

Serum differs from plasma primarily because serum lacks:

What role does the gel separator play in serum separator tubes (SSTs)?

What is the most critical step to take before centrifuging a red top tube after blood collection, and why?

For which analyte is a red top tube generally MOST appropriate?

Why are serum separator tubes (SSTs) generally NOT recommended for therapeutic drug monitoring?

What is the mechanism by which EDTA prevents blood coagulation?

A chemistry profile from a purple top (EDTA) tube shows a critically low calcium level (e.g., 2 mg/dL). What is the MOST likely explanation?

Why is a purple top (EDTA) tube considered a good choice for performing cell counts?

Lithium heparin is often preferred over sodium heparin for general chemistry profiles primarily because:

How does refrigeration help preserve glucose levels in blood samples?

A laboratory is evaluating a new diagnostic test for a rare disease. Which method would be MOST suitable for comparing the results of the new test with those of an established, highly accurate test when evaluating its performance?

Which measure is MOST critical to evaluate when choosing a screening test designed to identify a disease in its early stages, especially when the disease has severe consequences if left untreated?

A veterinary clinic is using a point-of-care instrument to measure blood glucose. The instrument has a built-in quality control system that performs regular internal checks. Despite this, what additional step is MOST important to consistently ensure the reliability and accuracy of the instrument's measurements?