II. Definitions

  1. Test Sensitivity
    1. Screening Test's ability to identify true disease
    2. A Test with high sensitivity has few False Negatives
    3. Independent of disease Prevalence in the community
    4. Sensitive Tests allow user to RULE OUT a condition (mnemonic "SNout")
  2. Recall
    1. Identical to the Test Sensitivity, but Recall term is used more in data science
    2. Reflects what percentage of relevant items are positive (not missed as False Negatives)
    3. See Test Precision (Positive Predictive Value)

III. Calculation

  1. Test Sensitivity
    1. True positive tests per total affected patients tested
    2. Test Sensitivity = P(positive test | disease)
      1. Where P (A | B) = Probability of A given B
    3. Expressed as a percentage
  2. False Negative Rate
    1. True cases missed by the Screening Test (test negative despite presence of condition)
    2. False Negative Rate = 1 - Test Sensitivity

IV. Example: A new Screening Test for Crohn's Disease

  1. Patients with known Crohn's Disease tested: 45
  2. Patients with known Crohn's Disease who have a positive test: 36
  3. Sensitivity = 36/45 or 80%

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Related Studies

Ontology: False Negative Reactions (C0015562)

Definition (MSH) Negative test results in subjects who possess the attribute for which the test is conducted. The labeling of diseased persons as healthy when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)
Concepts Laboratory or Test Result (T034)
MSH D005188
English False Negative Reaction, False Negative Reactions, Reaction, False Negative, Reactions, False Negative
Swedish Falskt negativa reaktioner
Czech falešně negativní reakce
Finnish Väärät negatiiviset tulokset
French Tests faussement négatifs, Faux négatifs, Réactions faussement négatives
Polish Wyniki fałszywie ujemne
Norwegian Falske negative reaksjoner
German Falsch-negative Reaktionen
Italian Reazioni falso-negative
Dutch Reactie, fals-negatieve
Portuguese Reações Falso-Negativas
Spanish Reacciones Falso Negativas

Ontology: sensitivity of measurement (C0681900)

Concepts Quantitative Concept (T081)
English sensitivity of measurement

Ontology: Diagnostic Sensitivity (C1511883)

Definition (NCI_NCI-GLOSS) The frequency with which a test yields a true positive result among individuals who actually have the disease or the gene mutation in question. A test with high sensitivity has a low false-negative rate and thus does a good job of correctly identifying affected individuals.
Definition (NCI) The probability that a test will produce a true postive result when used on effected subjects as compared to a reference or "gold standard". The sensitivity of a test can be determined by calculating: number of true positive results divided by the sum of true positive results plus number of false negative results.
Concepts Quantitative Concept (T081)
English Sensitivity, Sensitivity of Diagnostic Test, Diagnostic Sensitivity, sensitivity