Flashcards in Lab Medicine Deck (39)
how closely the test results correspond to the true value or “gold standard.”
How reproduce-able the results are with repeat testing of the same specimen
measures TN--> the percentage of persons WITHOUT the disease of interest with negative test results-->higher specificity of the test, the more likely it is that persons without the disease of interest will be excluded from consideration of having the disease
What kind of test is used to clinically rule IN the disease?
T/F: The lower the specificity, the higher the chance of a false positive result
measures TP --> higher the sensitivity, the more likely to detect people WITH the dz
What is used to clinically to rule OUT the presence of the disease in an individual
Measures concerning to estimation of the probability of the presence or absence of disease.
percent of persons with a positive test result who DO HAVE the disease in question
percentage of persons with a negative test result who DO NOT HAVE the disease in question
lab testing that identifies abnormalities that are NOT present.
lab testing that fails to identify abnormalities that ARE present.
the proportion of a population found to have a condition (typically a disease or risk factor) at a particular time.
Probability of a result in a patient with or without disease
Probability of negative test in non-diseased person/ Probability of negative test in a diseased person
the probability of the target disorder before a diagnostic test result is `known
the probability of the presence of a condition (disease) after a diagnostic test.
most accurate measure
descriptive values (ie: path report/ Chest Xray report)
five major reasons for ordering a laboratory measurement
1) Discover occult (not accompanied by readily discernible signs or symptoms) disease or recurrent disease
2) Confirm a suspected diagnosis
3) Differentiate among possible diagnoses
4) Determine the stage, activity, or severity of disease
5) Assess and monitor the effectiveness of therapy or treatment
Yes/No or Positive/Negative (ie: pregnancy test, rapid strep)
range of “normal” values
T/F: 1 in 20 “normal” tests will have test results outside of the reference range.
Basic Metabolic Profile (BMP):
common serum electrolytes (Na+, K+, Cl-), carbon dioxide content, blood urea nitrogen, Ca++, creatinine, and glucose
Complete Metabolic Profile (CMP):
all BMP components plus albumin, alanine aminotransferease (ALT), aspartate aminotransferease (AST), total bilirubin, and total protein
erythrocyte sedimentation test
non-specific test; increases in ESR (erythrocyte sedimentation rate) = infection, inflammation, and plasma cell dyscrasias
percentage volume of blood that is composed of erythrocytes (RBCs)
STAT laboratory tests
needed immediately; given highest priority