II. Definitions
- Test Sensitivity
- Screening Test's ability to identify true disease
- A Test with high sensitivity has few False Negatives
- Independent of disease Prevalence in the community
- Sensitive Tests allow user to RULE OUT a condition (mnemonic "SNout")
- Recall
- Identical to the Test Sensitivity, but Recall term is used more in data science
- Reflects what percentage of relevant items are positive (not missed as False Negatives)
- See Test Precision (Positive Predictive Value)
III. Calculation
- Test Sensitivity
- True positive tests per total affected patients tested
- Test Sensitivity = P(positive test | disease)
- Where P (A | B) = Probability of A given B
- Expressed as a percentage
- False Negative Rate
- True cases missed by the Screening Test (test negative despite presence of condition)
- False Negative Rate = 1 - Test Sensitivity
IV. Example: A new Screening Test for Crohn's Disease
- Patients with known Crohn's Disease tested: 45
- Patients with known Crohn's Disease who have a positive test: 36
- Sensitivity = 36/45 or 80%
V. References
- Hennekens (1987) Epidemiology Medicine, p.327-47
- Gates (2001) Am Fam Physician 63(3):513-22 [PubMed]
- MacLean (1996) Med Clin North Am 80(1):1-14 [PubMed]
- Nielsen (1999) Med Clin North Am 83(6):1323-37 [PubMed]
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Related Studies
| 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 |
| Russian | LOZHNOOTRITSATEL'NYE REAKTSII, ЛОЖНООТРИЦАТЕЛЬНЫЕ РЕАКЦИИ |
| 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 |
