3 - Diagnostic Accuracy in Clinical Laboratories

<p>Accuracy is the closeness of the measurement to the true value, while precision is the repeatability of the measurement. (A)</p> Signup and view all the answers

<p>To confirm results due to the overlap between populations at cut-off points. (C)</p> Signup and view all the answers

<p>All of the above (D)</p> Signup and view all the answers

<p>$(TP + TN) / (TP + TN + FP + FN)$ (A)</p> Signup and view all the answers

<p>To account for variations due to changes in diet and maintenance. (D)</p> Signup and view all the answers

<p>Materials like plastic can react with the analyte, skewing results. (D)</p> Signup and view all the answers

<p>The interval between specimen collection and analysis. (C)</p> Signup and view all the answers

<p>There were guidelines available on how to conduct studies establishing reference values. (A)</p> Signup and view all the answers

<p>Healthy values are measured in healthy populations, while patient values are measured in patients with diseases. (C)</p> Signup and view all the answers

<p>To replace the concept of normal values with a more accurate and standardized approach for interpreting blood analyte concentrations (B)</p> Signup and view all the answers

<p>Laboratory Technician's Preference (C)</p> Signup and view all the answers

<p>Higher Vitamin D levels through exposure to sunlight (A)</p> Signup and view all the answers

<p>Differences in sex and race may necessitate population-specific reference ranges. (D)</p> Signup and view all the answers

<p>Normal Values (C)</p> Signup and view all the answers

<p>1987 to 1991 (B)</p> Signup and view all the answers

<p>Helps in the clinical decision-making process (C)</p> Signup and view all the answers

<p>Because of the weather (C)</p> Signup and view all the answers

<p>Field of laboratory medicine (D)</p> Signup and view all the answers

<p>It can aid in standardization (C)</p> Signup and view all the answers

<p>A greater proportion of patients with positive test results who actually have the disease. (C)</p> Signup and view all the answers

<p>The test is missing many true positives. (C)</p> Signup and view all the answers

<p>False Negative (C)</p> Signup and view all the answers

<p>Sensitivity (B)</p> Signup and view all the answers

<p>The test's accuracy will decrease if the disease prevalence differs in the broader population. (C)</p> Signup and view all the answers

<p>Values, Limits, Intervals or Ranges (D)</p> Signup and view all the answers

<p>Decreased Sensitivity (A)</p> Signup and view all the answers

<p>The range of values considered normal for a test. (A)</p> Signup and view all the answers

<p>Increased false negatives decrease sensitivity (A)</p> Signup and view all the answers

<p>The prevalence of the disease/analyte varies (C)</p> Signup and view all the answers

<p>($TP + TN$) / ($TP + TN + FP + FN$) (A)</p> Signup and view all the answers

<p>It accurately identifies almost all individuals with the disease. (A)</p> Signup and view all the answers

<p>Sensitivity (A)</p> Signup and view all the answers

<p>The test correctly identifies someone who has the disease. (A)</p> Signup and view all the answers

<p>False Positives (A)</p> Signup and view all the answers

<p>The test will likely identify most individuals who have the disease. (A)</p> Signup and view all the answers

<p>128 (B)</p> Signup and view all the answers

<p>Test A, because it is less likely to miss infected individuals. (C)</p> Signup and view all the answers

<p>A reference test or method that is considered the most accurate for confirming a diagnosis. (A)</p> Signup and view all the answers

The degree to which a diagnostic test correctly identifies or excludes a condition.

The ability of a test to correctly identify true positives (TP).

The ability of a test to correctly identify true negatives (TN).

The best available method for confirming a diagnosis, used for comparison.

The formula to calculate diagnostic accuracy: (TN + TP) / (TN + TP + FP + FN).

Established values used to interpret test results, indicating normal or abnormal.

The process of selecting appropriate cut-off points for test results.

The measure of how often a model correctly classifies instances, calculated as (TN + TP) / (TN + TP + FP + FN).

The number of cases where the test correctly identifies the presence of disease.

The number of cases where the test correctly identifies the absence of disease.

The number of cases where the test incorrectly indicates the presence of disease.

The number of cases where the test fails to identify a disease that is present.

Clinical Laboratory Standard Institute, which publishes clinical guidelines.

International Federation of Clinical Chemistry, involved in laboratory practices.

Conditions required for storing samples before analysis.

Reference values differ based on whether individuals are healthy or diseased.

Variations in the concentrations of substances in the blood over time.

The outdated concept of average blood analyte levels which may not be accurate.

A system of names and terms used to standardize practices in laboratory testing.

External conditions that can affect blood analyte levels.

Variations in blood analyte levels based on age—children vs. elderly.

Variations in reference values based on genetic background, sex, and race.

The process of making informed choices based on laboratory test results.

Increased hemoglobin levels due to lower oxygen levels at high altitudes.

Concentrations of Vitamin D in the blood, often higher with increased sunlight exposure.

The probability that subjects with a positive test truly have the disease.

The probability that subjects with a negative test truly do not have the disease.

A test result that incorrectly indicates no disease when it is present.

Changing significant figures may lead to misclassification of test results.

A threshold set to distinguish between different test results for diagnosis.

A range of values used to interpret test results; indicates healthy limits.

Early tests performed on a small group to confirm a test's effectiveness.