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Positive and negative predictive values

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2670:. Usually publications stating PPV of a throat swab are reporting on the probability that this bacterium is present in the throat, rather than that the patient is ill from the bacteria found. If presence of this bacterium always resulted in a sore throat, then the PPV would be very useful. However the bacteria may colonise individuals in a harmless way and never result in infection or disease. Sore throats occurring in these individuals are caused by other agents such as a virus. In this situation the gold standard used in the evaluation study represents only the presence of bacteria (that might be harmless) but not a causal bacterial sore throat illness. It can be proven that this problem will affect positive predictive value far more than negative predictive value. To evaluate diagnostic tests where the gold standard looks only at potential causes of disease, one may use an extension of the predictive value termed the 133: 141: 2654:(LR+). Also, note that a critical assumption is that the tests must be independent. As described Balayla et al., repeating the same test may violate the this independence assumption and in fact "A more natural and reliable method to enhance the positive predictive value would be, when available, to use a different test with different parameters altogether after an initial positive result is obtained.". 36: 898: 526: 601: 299: 745: 435: 2662:
PPV is used to indicate the probability that in case of a positive test, that the patient really has the specified disease. However, there may be more than one cause for a disease and any single potential cause may not always result in the overt disease seen in a patient. There is potential to mix up
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Note that the PPV is not intrinsic to the test—it depends also on the prevalence. Due to the large effect of prevalence upon predictive values, a standardized approach has been proposed, where the PPV is normalized to a prevalence of 50%. PPV is directly proportional to the prevalence of the disease
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To overcome this problem, NPV and PPV should only be used if the ratio of the number of patients in the disease group and the number of patients in the healthy control group used to establish the NPV and PPV is equivalent to the prevalence of the diseases in the studied population, or, in case two
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The small positive predictive value (PPV = 10%) indicates that many of the positive results from this testing procedure are false positives. Thus it will be necessary to follow up any positive result with a more reliable test to obtain a more accurate assessment as to whether cancer is
616:" is the event that the test makes a negative prediction, and the subject has a positive result under the gold standard. With a perfect test, one which returns no false negatives, the value of the NPV is 1 (100%), and with a test which returns no true negatives the NPV value is zero. 546: 244: 2258:, below which the reliability of a positive screening test drops precipitously. That said, Balayla et al. showed that sequential testing overcomes the aforementioned Bayesian limitations and thus improves the reliability of screening tests. For a desired positive predictive value 2219:
or condition. In the above example, if the group of people tested had included a higher proportion of people with bowel cancer, then the PPV would probably come out higher and the NPV lower. If everybody in the group had bowel cancer, the PPV would be 100% and the NPV 0%.
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present. Nevertheless, such a test may be useful if it is inexpensive and convenient. The strength of the FOB screen test is instead in its negative predictive value — which, if negative for an individual, gives us a high confidence that its negative result is true.
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confers inherent limitations on the accuracy of screening tests as a function of disease prevalence or pre-test probability. It has been shown that a testing system can tolerate significant drops in prevalence, up to a certain well-defined point known as the
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results, respectively. The PPV and NPV describe the performance of a diagnostic test or other statistical measure. A high result can be interpreted as indicating the accuracy of such a statistic. The PPV and NPV are not intrinsic to the test (as
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disease groups are compared, if the ratio of the number of patients in disease group 1 and the number of patients in disease group 2 is equivalent to the ratio of the prevalences of the two diseases studied. Otherwise, positive and negative
2504: 893:{\displaystyle {\text{FOR}}=1-{\text{NPV}}={\frac {\text{Number of false negatives}}{{\text{Number of true negatives}}+{\text{Number of false negatives}}}}={\frac {\text{Number of false negatives}}{\text{Number of negative calls}}}} 521:{\displaystyle {\text{FDR}}=1-{\text{PPV}}={\frac {\text{Number of false positives}}{{\text{Number of true positives}}+{\text{Number of false positives}}}}={\frac {\text{Number of false positives}}{\text{Number of positive calls}}}} 318:" is the event that the test makes a positive prediction, and the subject has a negative result under the gold standard. The ideal value of the PPV, with a perfect test, is 1 (100%), and the worst possible value would be zero. 596:{\displaystyle {\text{NPV}}={\frac {\text{Number of true negatives}}{{\text{Number of true negatives}}+{\text{Number of false negatives}}}}={\frac {\text{Number of true negatives}}{\text{Number of negative calls}}}} 294:{\displaystyle {\text{PPV}}={\frac {\text{Number of true positives}}{{\text{Number of true positives}}+{\text{Number of false positives}}}}={\frac {\text{Number of true positives}}{\text{Number of positive calls}}}} 2663:
related target conditions of PPV and NPV, such as interpreting the PPV or NPV of a test as having a disease, when that PPV or NPV value actually refers only to a predisposition of having that disease.
2242:). Preferably, in such cases, a large group of equivalent individuals should be studied, in order to establish separate positive and negative predictive values for use of the test in such individuals. 740:{\displaystyle {\text{NPV}}={\frac {{\text{specificity}}\times (1-{\text{prevalence}})}{{\text{specificity}}\times (1-{\text{prevalence}})+(1-{\text{sensitivity}})\times {\text{prevalence}}}}} 2238:, with the PPV and NPV referring to the ones established by the control groups, and the post-test probabilities referring to the ones for the tested individual (as estimated, for example, by 806: 430:{\displaystyle {\text{PPV}}={\frac {{\text{sensitivity}}\times {\text{prevalence}}}{{\text{sensitivity}}\times {\text{prevalence}}+(1-{\text{specificity}})\times (1-{\text{prevalence}})}}} 53: 3299: 2302: 2766: 3028:"The Matthews correlation coefficient (MCC) is more reliable than balanced accuracy, bookmaker informedness, and markedness in two-class confusion matrix evaluation" 2357: 2644: 2579: 2559: 2530: 2349: 2276: 3174:"Etiologic predictive value of a rapid immunoassay for the detection of group A Streptococcus antigen from throat swabs in patients presenting with a sore throat" 2622: 2600: 2322: 917:
of the target condition is the same as the prevalence in the control group used to establish the negative predictive value, then the two are numerically equal.
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of having a condition than the control groups used to establish the PPV and NPV, the PPV and NPV are generally distinguished from the positive and negative
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of the target condition is the same as the prevalence in the control group used to establish the positive predictive value, the two are numerically equal.
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Gunnarsson, Ronny K.; Lanke, Jan (2002). "The predictive value of microbiologic diagnostic tests if asymptomatic carriers are present".
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Brooks, Harold; Brown, Barb; Ebert, Beth; Ferro, Chris; Jolliffe, Ian; Koh, Tieh-Yong; Roebber, Paul; Stephenson, David (2015-01-26).
2750: 2698: 2039: 1281: 119: 68: 2703: 1597: 612:" is the event that the test makes a negative prediction, and the subject has a negative result under the gold standard, and a " 2977:"The advantages of the Matthews correlation coefficient (MCC) over F1 score and accuracy in binary classification evaluation" 1884: 1061: 910: 201: 57: 3289: 2688: 1996: 1888: 934: 757: 624: 620: 326: 322: 93: 3155:
Jacques Balayla. Bayesian Updating and Sequential Testing: Overcoming Inferential Limitations of Screening Tests.
1581: 46: 3294: 2156: 2103: 2070: 2035: 1442: 1362: 1337: 1275: 161: 132: 3173: 2235: 975: 140: 3284: 1776: 1757: 1389: 956: 310:" is the event that the test makes a positive prediction, and the subject has a positive result under the 2708: 2683: 2172: 1975: 1712: 1483: 212: 3172:
Orda, Ulrich; Gunnarsson, Ronny K; Orda, Sabine; Fitzgerald, Mark; Rofe, Geoffry; Dargan, Anna (2016).
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Type I error: A test result which wrongly indicates that a particular condition or attribute is present
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Type II error: A test result which wrongly indicates that a particular condition or attribute is absent
2895:"Evaluation: From Precision, Recall and F-Measure to ROC, Informedness, Markedness & Correlation" 2693: 2255: 2231: 2140: 1414: 988: 914: 446: 311: 233: 216: 205: 2054: 1971: 1903: 1309: 1217: 1168: 1099: 1065: 3241: 2856: 2760: 2000: 1880: 1744: 1732: 1720: 1211: 1057: 182: 178: 2281: 2876:"Data Science for Business: What You Need to Know about Data Mining and Data-Analytic Thinking" 2499:{\displaystyle n_{i}=\lim _{k\to \rho }\left\lceil {\frac {\ln \left}{\ln \left}}\right\rceil } 3233: 3198: 3133: 3059: 3008: 2929: 2814: 2746: 2742: 2713: 2250: 1719:
estimates may be obtained. In contrast, the sensitivity and specificity can be estimated from
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Note that the positive and negative predictive values can only be estimated using data from a
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are more accurate than NPV and PPV, because likelihood ratios do not depend on prevalence.
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Of note, the denominator of the above equation is the natural logarithm of the positive
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A test result that correctly indicates the presence of a condition or characteristic
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A test result that correctly indicates the absence of a condition or characteristic
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rather refers to a probability for an individual. Still, if the individual's
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generally refers to what is established by control groups, while a negative
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An example is the microbiological throat swab used in patients with a
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refers to a probability for an individual. Still, if the individual's
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respectively) are the proportions of positive and negative results in
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generally refers to what is established by control groups, while a
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Ting, Kai Ming (2011). Sammut, Claude; Webb, Geoffrey I. (eds.).
3112:"Standardizing predictive values in diagnostic imaging research" 29: 27:
Statistical measures of whether a finding is likely to be true
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Collaboration for Australian Weather and Climate Research
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is the number of testing iterations necessary to achieve
939: 2632: 2610: 2588: 2567: 2540: 2518: 2360: 2330: 2310: 2284: 2264: 832: 760: 642: 549: 460: 344: 247: 1070:probability of detection, hit rate, 60:. Unsourced material may be challenged and removed. 2638: 2616: 2594: 2573: 2553: 2524: 2498: 2343: 2316: 2296: 2270: 892: 800: 739: 595: 520: 429: 293: 2778: 2776: 2733:Fletcher, Robert H. Fletcher; Suzanne W. (2005). 1622:Threat score (TS), critical success index (CSI), 2375: 2230:When an individual being tested has a different 801:{\displaystyle {\text{NPV}}={\frac {TN}{TN+FN}}} 3026:Chicco D, Toetsch N, Jurman G (February 2021). 1715:or other population-based study in which valid 1685:the number of real negative cases in the data 1658:the number of real positive cases in the data 538:The negative predictive value is defined as: 8: 3181:International Journal of Infectious Diseases 2765:: CS1 maint: multiple names: authors list ( 2874:Provost, Foster; Tom Fawcett (2013-08-01). 2737:Clinical epidemiology : the essentials 1174:probability of false alarm, 144:Positive and negative predictive values - 2 3161:https://doi.org/10.1186/s12911-021-01738-w 925:The following diagram illustrates how the 3300:Summary statistics for contingency tables 3192: 3127: 3094: 3053: 3043: 3002: 2992: 2808: 2631: 2609: 2587: 2566: 2545: 2539: 2517: 2467: 2407: 2394: 2378: 2365: 2359: 2335: 2329: 2324:, the number of positive test iterations 2309: 2283: 2263: 880: 869: 861: 855: 847: 833: 831: 769: 761: 759: 729: 718: 698: 681: 671: 654: 651: 643: 641: 583: 572: 564: 558: 550: 548: 508: 497: 489: 483: 475: 461: 459: 416: 396: 379: 371: 364: 356: 353: 345: 343: 281: 270: 262: 256: 248: 246: 120:Learn how and when to remove this message 69:"Positive and negative predictive values" 2899:Journal of Machine Learning Technologies 1737: 905:Although sometimes used synonymously, a 232:The positive predictive value (PPV), or 215:, the PPV statistic is often called the 196:Although sometimes used synonymously, a 189:. Both PPV and NPV can be derived using 139: 131: 2785:"Diagnostic tests 2: Predictive values" 2725: 1651: 150:positive and negative predictive values 136:Positive and negative predictive values 2758: 3151: 3149: 3147: 3116:Journal of Magnetic Resonance Imaging 7: 58:adding citations to reliable sources 3079:"Classification assessment methods" 2975:Chicco D, Jurman G (January 2020). 2957:. World Meteorological Organisation 619:The NPV can also be computed from 321:The PPV can also be computed from 25: 3083:Applied Computing and Informatics 2834:"An Introduction to ROC Analysis" 2699:Relevance (information retrieval) 813:The complement of the NPV is the 445:The complement of the PPV is the 2918:Encyclopedia of machine learning 2704:Receiver-operator characteristic 2304:, that approaches some constant 1598:Matthews correlation coefficient 34: 1861:(2030 × 1.48% × 67%) 534:Negative predictive value (NPV) 228:Positive predictive value (PPV) 45:needs additional citations for 3122:(2): 505, author reply 506–7. 2783:Altman, DG; Bland, JM (1994). 2445: 2433: 2425: 2413: 2382: 723: 709: 703: 689: 676: 662: 421: 407: 401: 387: 185:are); they depend also on the 1: 2893:Powers, David M. W. (2011). 2853:10.1016/j.patrec.2005.10.010 935:sensitivity, and specificity 2841:Pattern Recognition Letters 2689:Sensitivity and specificity 2658:Different target conditions 2127:= (10 / 30) / (1820 / 2000) 1152:false alarm, overestimation 980:bookmaker informedness (BM) 3316: 3194:10.1016/j.ijid.2016.02.002 3110:Heston, Thomas F. (2011). 3077:Tharwat A. (August 2018). 3045:10.1186/s13040-021-00244-z 2672:Etiologic Predictive Value 2297:{\displaystyle \rho <1} 2094:= (20 / 30) / (180 / 2000) 1982:probability of false alarm 1873:(2030 × 1.48% × 3096:10.1016/j.aci.2018.08.003 2994:10.1186/s12864-019-6413-7 2926:10.1007/978-0-387-30164-8 2171: 2157:Negative predictive value 2104:Negative likelihood ratio 2071:Positive likelihood ratio 2036:Positive predictive value 2017: 1825: 1750: 1742: 1740: 1621: 1443:Negative predictive value 1363:Negative likelihood ratio 1338:Positive likelihood ratio 1276:Positive predictive value 1247: 1020: 951: 946: 942: 931:negative predictive value 927:positive predictive value 907:negative predictive value 883:Number of false negatives 871:Number of false negatives 858:Number of false negatives 574:Number of false negatives 511:Number of false positives 499:Number of false positives 486:Number of false positives 272:Number of false positives 198:positive predictive value 18:Negative predictive value 3157:BMC Med Inform Decis Mak 2801:10.1136/bmj.309.6947.102 2214:Other individual factors 886:Number of negative calls 863:Number of true negatives 589:Number of negative calls 586:Number of true negatives 566:Number of true negatives 561:Number of true negatives 514:Number of positive calls 491:Number of true positives 287:Number of positive calls 284:Number of true positives 264:Number of true positives 259:Number of true positives 2236:post-test probabilities 1805:precision × recall 1513:Balanced accuracy (BA) 1110:type II error 971:Predicted negative (PN) 966:Predicted positive (PP) 3218:Statistics in Medicine 2640: 2618: 2596: 2575: 2555: 2526: 2500: 2345: 2318: 2298: 2272: 1184:type I error 894: 802: 741: 597: 522: 431: 295: 145: 137: 3259:Gunnarsson, Ronny K. 2832:Fawcett, Tom (2006). 2709:Diagnostic odds ratio 2684:Binary classification 2646:is disease prevalence 2641: 2639:{\displaystyle \phi } 2619: 2597: 2576: 2574:{\displaystyle \rho } 2556: 2554:{\displaystyle n_{i}} 2527: 2525:{\displaystyle \rho } 2501: 2346: 2344:{\displaystyle n_{i}} 2319: 2299: 2273: 2271:{\displaystyle \rho } 2173:Diagnostic odds ratio 1906:(FNR), miss rate 1713:cross-sectional study 1616:FNR × FPR × FOR × FDR 1607:TPR × TNR × PPV × NPV 1582:Fowlkes–Mallows index 1053:miss, underestimation 911:post-test probability 895: 803: 742: 598: 523: 432: 296: 213:information retrieval 202:post-test probability 143: 135: 2694:False discovery rate 2630: 2608: 2586: 2565: 2538: 2516: 2358: 2328: 2308: 2282: 2262: 2256:prevalence threshold 2232:pre-test probability 2163:= 1820 / (10 + 1820) 2141:False discovery rate 1966:(100% − 1.48%) 1946:(100% − 1.48%) 1930:(100% − 1.48%) 1849:(2030 × 1.48%) 1783:= (20 + 1820) / 2030 1721:case-control studies 1415:False discovery rate 989:Prevalence threshold 915:pre-test probability 830: 758: 640: 547: 458: 447:false discovery rate 342: 245: 206:pre-test probability 54:improve this article 2880:O'Reilly Media, Inc 2055:False omission rate 1972:False positive rate 1904:False negative rate 1747:screen test outcome 1310:False omission rate 1169:False positive rate 1100:False negative rate 948:Predicted condition 817:false omission rate 442:cf. Bayes' theorem 3290:Statistical ratios 3265:Science Network TV 3129:10.1002/jmri.22466 2636: 2624:is the specificity 2614: 2602:is the sensitivity 2592: 2571: 2551: 2532:is the desired PPV 2522: 2496: 2389: 2341: 2314: 2294: 2268: 2147:= 180 / (20 + 180) 2061:= 10 / (10 + 1820) 2001:true negative rate 1950:(100% − 91%) 1881:True positive rate 1875:(100% − 67%) 1811:precision + recall 1781:= (TP + TN) / pop. 1745:Fecal occult blood 1733:fecal occult blood 1220:(SPC), selectivity 1212:True negative rate 1058:True positive rate 890: 798: 737: 593: 518: 427: 333:of the condition: 291: 183:true negative rate 179:true positive rate 146: 138: 2935:978-0-387-30164-8 2714:Sensitivity index 2617:{\displaystyle b} 2595:{\displaystyle a} 2490: 2483: 2449: 2374: 2317:{\displaystyle k} 2246:Bayesian updating 2240:likelihood ratios 2225:likelihood ratios 2202: 2201: 2045:= 20 / (20 + 180) 1648: 1647: 1164:correct rejection 888: 887: 884: 875: 872: 864: 859: 850: 836: 796: 764: 735: 732: 721: 701: 684: 674: 657: 646: 591: 590: 587: 578: 575: 567: 562: 553: 516: 515: 512: 503: 500: 492: 487: 478: 464: 425: 419: 399: 382: 374: 367: 359: 348: 289: 288: 285: 276: 273: 265: 260: 251: 130: 129: 122: 104: 16:(Redirected from 3307: 3295:Categorical data 3269: 3268: 3261:"EPV Calculator" 3256: 3250: 3249: 3230:10.1002/sim.1119 3213: 3207: 3206: 3196: 3178: 3169: 3163: 3153: 3142: 3141: 3131: 3107: 3101: 3100: 3098: 3074: 3068: 3067: 3057: 3047: 3023: 3017: 3016: 3006: 2996: 2972: 2966: 2965: 2963: 2962: 2946: 2940: 2939: 2913: 2907: 2906: 2890: 2884: 2883: 2871: 2865: 2864: 2838: 2829: 2823: 2822: 2812: 2780: 2771: 2770: 2764: 2756: 2740: 2730: 2652:likelihood ratio 2645: 2643: 2642: 2637: 2623: 2621: 2620: 2615: 2601: 2599: 2598: 2593: 2580: 2578: 2577: 2572: 2560: 2558: 2557: 2552: 2550: 2549: 2531: 2529: 2528: 2523: 2505: 2503: 2502: 2497: 2495: 2491: 2489: 2488: 2484: 2482: 2468: 2455: 2454: 2450: 2448: 2428: 2408: 2395: 2388: 2370: 2369: 2350: 2348: 2347: 2342: 2340: 2339: 2323: 2321: 2320: 2315: 2303: 2301: 2300: 2295: 2277: 2275: 2274: 2269: 2192: 2190: 2189: 2186: 2183: 2161:= TN / (FN + TN) 2145:= FP / (TP + FP) 2125: 2123: 2122: 2119: 2116: 2108: 2092: 2090: 2089: 2086: 2083: 2075: 2059:= FN / (FN + TN) 2043:= TP / (TP + FP) 1983: 1978: 1967: 1960: 1951: 1947: 1940: 1931: 1922:Actual condition 1876: 1869: 1857: 1843:Actual condition 1815: 1813: 1812: 1809: 1806: 1758:Total population 1738: 1704: 1701: 1695: 1692: 1686: 1683: 1677: 1674: 1668: 1665: 1659: 1656: 1644: 1643: 1641: 1640: 1637: 1634: 1619: 1618: 1617: 1610: 1609: 1608: 1594: 1593: 1592: 1578: 1577: 1575: 1574: 1571: 1568: 1560: 1559: 1557: 1556: 1553: 1550: 1532: 1531: 1529: 1528: 1525: 1522: 1508: 1507: 1505: 1504: 1501: 1498: 1487: 1480: 1476: 1475:deltaP (Δp) 1467: 1464: 1463: 1461: 1460: 1457: 1454: 1439: 1436: 1435: 1433: 1432: 1429: 1426: 1411: 1410: 1408: 1407: 1404: 1401: 1384: 1383: 1381: 1380: 1377: 1374: 1359: 1358: 1356: 1355: 1352: 1349: 1334: 1331: 1330: 1328: 1327: 1324: 1321: 1306: 1303: 1302: 1300: 1299: 1296: 1293: 1284: 1279: 1271: 1270: 1268: 1267: 1264: 1261: 1243: 1240: 1239: 1237: 1236: 1233: 1230: 1221: 1208: 1205: 1204: 1202: 1201: 1198: 1195: 1186: 1180: 1178: 1165: 1153: 1134: 1131: 1130: 1128: 1127: 1124: 1121: 1112: 1106: 1096: 1093: 1092: 1090: 1089: 1086: 1083: 1074: 1054: 1042: 1023:Actual condition 1016: 1015: 1013: 1012: 1009: 1006: 1004: 1003: 985: 981: 962: 957:Total population 940: 899: 897: 896: 891: 889: 885: 882: 881: 876: 874: 873: 870: 865: 862: 857: 856: 851: 848: 837: 834: 819: 818: 807: 805: 804: 799: 797: 795: 778: 770: 765: 762: 746: 744: 743: 738: 736: 734: 733: 730: 722: 719: 702: 699: 685: 682: 679: 675: 672: 658: 655: 652: 647: 644: 602: 600: 599: 594: 592: 588: 585: 584: 579: 577: 576: 573: 568: 565: 560: 559: 554: 551: 527: 525: 524: 519: 517: 513: 510: 509: 504: 502: 501: 498: 493: 490: 485: 484: 479: 476: 465: 462: 436: 434: 433: 428: 426: 424: 420: 417: 400: 397: 383: 380: 375: 372: 369: 368: 365: 360: 357: 354: 349: 346: 300: 298: 297: 292: 290: 286: 283: 282: 277: 275: 274: 271: 266: 263: 258: 257: 252: 249: 236:, is defined as 166:diagnostic tests 125: 118: 114: 111: 105: 103: 62: 38: 30: 21: 3315: 3314: 3310: 3309: 3308: 3306: 3305: 3304: 3275: 3274: 3273: 3272: 3258: 3257: 3253: 3224:(12): 1773–85. 3215: 3214: 3210: 3187:(April): 32–5. 3176: 3171: 3170: 3166: 3154: 3145: 3109: 3108: 3104: 3076: 3075: 3071: 3025: 3024: 3020: 2987:(1): 6-1–6-13. 2974: 2973: 2969: 2960: 2958: 2948: 2947: 2943: 2936: 2915: 2914: 2910: 2892: 2891: 2887: 2873: 2872: 2868: 2836: 2831: 2830: 2826: 2782: 2781: 2774: 2757: 2753: 2732: 2731: 2727: 2722: 2680: 2660: 2628: 2627: 2606: 2605: 2584: 2583: 2563: 2562: 2541: 2536: 2535: 2514: 2513: 2472: 2463: 2456: 2429: 2409: 2403: 2396: 2390: 2361: 2356: 2355: 2331: 2326: 2325: 2306: 2305: 2280: 2279: 2260: 2259: 2248: 2216: 2211: 2198: 2193: 2187: 2184: 2181: 2180: 2178: 2169: 2164: 2162: 2153: 2148: 2146: 2133: 2128: 2126: 2120: 2117: 2114: 2113: 2111: 2106: 2100: 2095: 2093: 2087: 2084: 2081: 2080: 2078: 2073: 2067: 2062: 2060: 2051: 2046: 2044: 2032: 2027: 2025: 2013: 2008: 2006: 1999:, selectivity, 1993: 1988: 1986: 1981: 1976: 1965: 1963: 1961: 1955: 1949: 1945: 1943: 1941: 1935: 1929: 1927: 1925: 1923: 1917: 1912: 1910: 1907: 1900: 1895: 1893: 1874: 1872: 1870: 1864: 1860: 1858: 1852: 1848: 1846: 1844: 1834: 1832: 1828: 1821: 1816: 1810: 1807: 1804: 1803: 1801: 1796: 1789: 1784: 1782: 1760: 1729: 1710: 1708: 1707: 1702: 1698: 1693: 1689: 1684: 1680: 1675: 1671: 1666: 1662: 1657: 1653: 1638: 1635: 1632: 1631: 1629: 1627: 1626: 1615: 1613: 1611: 1606: 1604: 1602: 1601: 1590: 1588: 1586: 1585: 1572: 1569: 1566: 1565: 1563: 1561: 1554: 1551: 1548: 1547: 1545: 1543: 1542: 1539: 1526: 1523: 1520: 1519: 1517: 1515: 1514: 1502: 1499: 1496: 1495: 1493: 1491: 1490: 1485: 1479:= PPV + NPV − 1 1478: 1477: 1474: 1465: 1458: 1455: 1452: 1451: 1449: 1447: 1446: 1437: 1430: 1427: 1424: 1423: 1421: 1419: 1418: 1405: 1402: 1399: 1398: 1396: 1394: 1393: 1378: 1375: 1372: 1371: 1369: 1367: 1366: 1353: 1350: 1347: 1346: 1344: 1342: 1341: 1332: 1325: 1322: 1319: 1318: 1316: 1314: 1313: 1304: 1297: 1294: 1291: 1290: 1288: 1286: 1285: 1280: 1274: 1265: 1262: 1259: 1258: 1256: 1254: 1253: 1241: 1234: 1231: 1228: 1227: 1225: 1223: 1222: 1216: 1215: 1206: 1199: 1196: 1193: 1192: 1190: 1188: 1187: 1182: 1181: 1176: 1173: 1172: 1163: 1162: 1151: 1150: 1132: 1125: 1122: 1119: 1118: 1116: 1114: 1113: 1108: 1107: 1104: 1103: 1094: 1087: 1084: 1081: 1080: 1078: 1076: 1075: 1069: 1052: 1051: 1040: 1039: 1025: 1010: 1007: 1001: 999: 998: 997: 995: 993: 992: 984:= TPR + TNR − 1 983: 982: 979: 960: 959: 923: 860: 828: 827: 816: 815: 779: 771: 756: 755: 680: 653: 638: 637: 563: 545: 544: 536: 488: 456: 455: 370: 355: 340: 339: 261: 243: 242: 230: 225: 126: 115: 109: 106: 63: 61: 51: 39: 28: 23: 22: 15: 12: 11: 5: 3313: 3311: 3303: 3302: 3297: 3292: 3287: 3277: 3276: 3271: 3270: 3251: 3208: 3164: 3159:22, 6 (2022). 3143: 3102: 3069: 3032:BioData Mining 3018: 2967: 2941: 2934: 2908: 2885: 2866: 2847:(8): 861–874. 2824: 2772: 2751: 2724: 2723: 2721: 2718: 2717: 2716: 2711: 2706: 2701: 2696: 2691: 2686: 2679: 2676: 2659: 2656: 2648: 2647: 2635: 2625: 2613: 2603: 2591: 2581: 2570: 2548: 2544: 2533: 2521: 2507: 2506: 2494: 2487: 2481: 2478: 2475: 2471: 2466: 2462: 2459: 2453: 2447: 2444: 2441: 2438: 2435: 2432: 2427: 2424: 2421: 2418: 2415: 2412: 2406: 2402: 2399: 2393: 2387: 2384: 2381: 2377: 2373: 2368: 2364: 2338: 2334: 2313: 2293: 2290: 2287: 2267: 2251:Bayes' theorem 2247: 2244: 2215: 2212: 2210: 2207: 2200: 2199: 2176: 2170: 2160: 2154: 2144: 2138: 2135: 2134: 2109: 2101: 2076: 2068: 2058: 2052: 2042: 2033: 2023: 2018: 2015: 2014: 2004: 1994: 1984: 1969: 1953: 1937:False positive 1933: 1919: 1918: 1908: 1901: 1891: 1878: 1866:False negative 1862: 1850: 1841: 1823: 1822: 1799: 1794: 1790: 1780: 1774: 1768: 1762: 1761:(pop.) = 2030 1755: 1752: 1751: 1749: 1741: 1728: 1727:Worked example 1725: 1706: 1705: 1696: 1687: 1678: 1669: 1660: 1650: 1649: 1646: 1645: 1620: 1595: 1579: 1573:2 TP + FP + FN 1537: 1533: 1510: 1509: 1481: 1468: 1440: 1412: 1386: 1385: 1360: 1335: 1307: 1272: 1248: 1245: 1244: 1209: 1166: 1154: 1146:False positive 1142: 1136: 1135: 1105:miss rate 1097: 1055: 1047:False negative 1043: 1031: 1026: 1021: 1018: 1017: 986: 973: 968: 963: 953: 952: 950: 945: 943: 922: 919: 903: 902: 901: 900: 879: 868: 854: 846: 843: 840: 811: 810: 809: 808: 794: 791: 788: 785: 782: 777: 774: 768: 750: 749: 748: 747: 728: 725: 717: 714: 711: 708: 705: 697: 694: 691: 688: 678: 670: 667: 664: 661: 650: 614:false negative 606: 605: 604: 603: 582: 571: 557: 535: 532: 531: 530: 529: 528: 507: 496: 482: 474: 471: 468: 440: 439: 438: 437: 423: 415: 412: 409: 406: 403: 395: 392: 389: 386: 378: 363: 352: 316:false positive 304: 303: 302: 301: 280: 269: 255: 229: 226: 224: 221: 191:Bayes' theorem 128: 127: 42: 40: 33: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 3312: 3301: 3298: 3296: 3293: 3291: 3288: 3286: 3285:Biostatistics 3283: 3282: 3280: 3266: 3262: 3255: 3252: 3247: 3243: 3239: 3235: 3231: 3227: 3223: 3219: 3212: 3209: 3204: 3200: 3195: 3190: 3186: 3182: 3175: 3168: 3165: 3162: 3158: 3152: 3150: 3148: 3144: 3139: 3135: 3130: 3125: 3121: 3117: 3113: 3106: 3103: 3097: 3092: 3088: 3084: 3080: 3073: 3070: 3065: 3061: 3056: 3051: 3046: 3041: 3037: 3033: 3029: 3022: 3019: 3014: 3010: 3005: 3000: 2995: 2990: 2986: 2982: 2978: 2971: 2968: 2956: 2952: 2945: 2942: 2937: 2931: 2927: 2923: 2919: 2912: 2909: 2904: 2900: 2896: 2889: 2886: 2881: 2877: 2870: 2867: 2862: 2858: 2854: 2850: 2846: 2842: 2835: 2828: 2825: 2820: 2816: 2811: 2806: 2802: 2798: 2795:(6947): 102. 2794: 2790: 2786: 2779: 2777: 2773: 2768: 2762: 2754: 2752:0-7817-5215-9 2748: 2744: 2739: 2738: 2729: 2726: 2719: 2715: 2712: 2710: 2707: 2705: 2702: 2700: 2697: 2695: 2692: 2690: 2687: 2685: 2682: 2681: 2677: 2675: 2673: 2669: 2664: 2657: 2655: 2653: 2633: 2626: 2611: 2604: 2589: 2582: 2568: 2546: 2542: 2534: 2519: 2512: 2511: 2510: 2492: 2485: 2479: 2476: 2473: 2469: 2464: 2460: 2457: 2451: 2442: 2439: 2436: 2430: 2422: 2419: 2416: 2410: 2404: 2400: 2397: 2391: 2385: 2379: 2371: 2366: 2362: 2354: 2353: 2352: 2336: 2332: 2311: 2291: 2288: 2285: 2265: 2257: 2252: 2245: 2243: 2241: 2237: 2233: 2228: 2226: 2220: 2213: 2208: 2206: 2197: 2174: 2168: 2158: 2155: 2152: 2142: 2139: 2137: 2136: 2132: 2105: 2102: 2099: 2072: 2069: 2066: 2056: 2053: 2050: 2041: 2037: 2034: 2031: 2022: 2019: 2016: 2012: 2007:= 1820 / 2000 2002: 1998: 1995: 1992: 1979: 1973: 1970: 1964:(2030 × 1958: 1957:True negative 1954: 1944:(2030 × 1938: 1934: 1928:(2030 × 1924:negative (AN) 1921: 1920: 1916: 1905: 1902: 1899: 1890: 1886: 1882: 1879: 1867: 1863: 1855: 1854:True positive 1851: 1845:positive (AP) 1842: 1840: 1838: 1833:(as confirmed 1831: 1827:Patients with 1824: 1820: 1798: 1791: 1788: 1778: 1775: 1773: 1770:Test outcome 1769: 1767: 1764:Test outcome 1763: 1759: 1756: 1754: 1753: 1748: 1746: 1739: 1736: 1734: 1726: 1724: 1722: 1718: 1714: 1700: 1697: 1691: 1688: 1682: 1679: 1673: 1670: 1664: 1661: 1655: 1652: 1625: 1624:Jaccard index 1599: 1596: 1583: 1580: 1541: 1534: 1512: 1511: 1488: 1482: 1472: 1469: 1444: 1441: 1416: 1413: 1391: 1388: 1387: 1364: 1361: 1339: 1336: 1311: 1308: 1283: 1277: 1273: 1252: 1249: 1246: 1219: 1213: 1210: 1185: 1179: 1170: 1167: 1160: 1159: 1158:True negative 1155: 1148: 1147: 1143: 1141: 1138: 1137: 1111: 1101: 1098: 1073: 1067: 1063: 1059: 1056: 1049: 1048: 1044: 1037: 1036: 1035:True positive 1032: 1030: 1027: 1024: 1019: 990: 987: 977: 974: 972: 969: 967: 964: 958: 955: 954: 949: 944: 941: 938: 937:are related. 936: 932: 928: 920: 918: 916: 912: 908: 877: 866: 852: 844: 841: 838: 826: 825: 824: 823: 822: 820: 792: 789: 786: 783: 780: 775: 772: 766: 754: 753: 752: 751: 726: 715: 712: 706: 695: 692: 686: 668: 665: 659: 648: 636: 635: 634: 633: 632: 630: 626: 622: 617: 615: 611: 610:true negative 580: 569: 555: 543: 542: 541: 540: 539: 533: 505: 494: 480: 472: 469: 466: 454: 453: 452: 451: 450: 448: 443: 413: 410: 404: 393: 390: 384: 376: 361: 350: 338: 337: 336: 335: 334: 332: 328: 324: 319: 317: 313: 312:gold standard 309: 308:true positive 278: 267: 253: 241: 240: 239: 238: 237: 235: 227: 222: 220: 218: 214: 209: 207: 203: 199: 194: 192: 188: 184: 180: 175: 174:true negative 171: 170:true positive 167: 163: 159: 155: 151: 142: 134: 124: 121: 113: 102: 99: 95: 92: 88: 85: 81: 78: 74: 71: –  70: 66: 65:Find sources: 59: 55: 49: 48: 43:This article 41: 37: 32: 31: 19: 3264: 3254: 3221: 3217: 3211: 3184: 3180: 3167: 3156: 3119: 3115: 3105: 3086: 3082: 3072: 3035: 3031: 3021: 2984: 2981:BMC Genomics 2980: 2970: 2959:. Retrieved 2954: 2944: 2920:. Springer. 2917: 2911: 2902: 2898: 2888: 2879: 2869: 2844: 2840: 2827: 2792: 2788: 2736: 2728: 2665: 2661: 2649: 2508: 2249: 2229: 2221: 2217: 2203: 2195: 2166: 2150: 2130: 2097: 2064: 2048: 2029: 2010: 1990: 1987:= 180 / 2000 1968:× 91%) 1956: 1936: 1914: 1897: 1865: 1853: 1830:bowel cancer 1826: 1818: 1786: 1771: 1765: 1743: 1731:Suppose the 1730: 1709: 1699: 1690: 1681: 1672: 1663: 1654: 1639:TP + FN + FP 1156: 1144: 1140:Negative (N) 1139: 1045: 1033: 1029:Positive (P) 1028: 1022: 976:Informedness 970: 965: 947: 930: 926: 924: 921:Relationship 906: 904: 814: 812: 618: 607: 537: 444: 441: 320: 305: 231: 210: 197: 195: 157: 153: 149: 147: 116: 107: 97: 90: 83: 76: 64: 52:Please help 47:verification 44: 3089:: 168–192. 2905:(1): 37–63. 2668:sore throat 2351:needed is: 2107:(LR−) 2026:= 30 / 2030 2024:= AP / pop. 1997:Specificity 1889:sensitivity 1800:= 2 × 1549:2 PPV × TPR 1484:Diagnostic 1218:specificity 1066:sensitivity 720:sensitivity 683:specificity 656:specificity 625:specificity 621:sensitivity 398:specificity 373:sensitivity 358:sensitivity 327:specificity 323:sensitivity 3279:Categories 3038:(13): 13. 2961:2019-07-17 2720:References 2021:Prevalence 1717:prevalence 1486:odds ratio 1471:Markedness 1251:Prevalence 731:prevalence 700:prevalence 673:prevalence 629:prevalence 418:prevalence 381:prevalence 366:prevalence 331:prevalence 329:, and the 223:Definition 187:prevalence 162:statistics 110:March 2012 80:newspapers 2761:cite book 2634:ϕ 2569:ρ 2520:ρ 2477:− 2461:⁡ 2440:− 2431:ϕ 2420:− 2417:ϕ 2401:⁡ 2386:ρ 2383:→ 2286:ρ 2266:ρ 2188:LR− 2040:precision 2005:= TN / AN 1985:= FP / AN 1911:= 10 / 30 1909:= FN / AP 1894:= 20 / 30 1892:= TP / AP 1837:endoscopy 1591:PPV × TPR 1555:PPV + TPR 1521:TPR + TNR 1466:= 1 − FOR 1438:= 1 − PPV 1333:= 1 − NPV 1305:= 1 − FDR 1282:precision 1242:= 1 − FPR 1207:= 1 − TNR 1133:= 1 − TPR 1095:= 1 − FNR 1011:TPR - FPR 1002:TPR × FPR 845:− 727:× 716:− 696:− 687:× 669:− 660:× 608:where a " 473:− 414:− 405:× 394:− 377:× 362:× 314:, and a " 306:where a " 234:precision 217:precision 168:that are 3246:26163122 3238:12111911 3203:26873279 3138:21274995 3064:33541410 3013:31898477 2678:See also 2493:⌉ 2392:⌈ 2278:, where 2209:Problems 2194:≈ 2165:≈ 2129:≈ 2096:≈ 2063:≈ 2028:≈ 1977:fall-out 1913:≈ 1896:≈ 1785:≈ 1777:Accuracy 1772:negative 1766:positive 1390:Accuracy 1177:fall-out 3055:7863449 3004:6941312 2861:2027090 2819:8038641 2810:2540558 2191:⁠ 2179:⁠ 2124:⁠ 2112:⁠ 2091:⁠ 2079:⁠ 2038:(PPV), 1974:(FPR), 1948:× 1883:(TPR), 1814:⁠ 1802:⁠ 1642:⁠ 1630:⁠ 1614:√ 1605:√ 1589:√ 1576:⁠ 1564:⁠ 1558:⁠ 1546:⁠ 1530:⁠ 1518:⁠ 1506:⁠ 1494:⁠ 1462:⁠ 1450:⁠ 1434:⁠ 1422:⁠ 1409:⁠ 1400:TP + TN 1397:⁠ 1382:⁠ 1370:⁠ 1357:⁠ 1345:⁠ 1329:⁠ 1317:⁠ 1301:⁠ 1289:⁠ 1269:⁠ 1257:⁠ 1238:⁠ 1226:⁠ 1214:(TNR), 1203:⁠ 1191:⁠ 1171:(FPR), 1129:⁠ 1117:⁠ 1102:(FNR), 1091:⁠ 1079:⁠ 1068:(SEN), 1060:(TPR), 1014:⁠ 1000:√ 996:⁠ 961:= P + N 821:(FOR): 449:(FDR): 94:scholar 3244:  3236:  3201:  3136:  3062:  3052:  3011:  3001:  2932:  2859:  2817:  2807:  2749:  2509:where 2175:(DOR) 2167:99.45% 1962:= 1820 1926:= 2000 1885:recall 1787:90.64% 1779:(ACC) 1600:(MCC) 1489:(DOR) 1473:(MK), 1445:(NPV) 1417:(FDR) 1392:(ACC) 1365:(LR−) 1340:(LR+) 1312:(FOR) 1278:(PPV), 1161:(TN), 1149:(FP), 1062:recall 1050:(FN), 1038:(TP), 627:, and 96:  89:  82:  75:  67:  3242:S2CID 3177:(PDF) 2857:S2CID 2837:(PDF) 2159:(NPV) 2151:90.0% 2143:(FDR) 2131:0.366 2074:(LR+) 2065:0.55% 2057:(FOR) 2030:1.48% 2003:(TNR) 1942:= 180 1915:33.3% 1898:66.7% 1819:0.174 1797:score 1584:(FM) 1540:score 1406:P + N 1266:P + N 1072:power 1005:- FPR 991:(PT) 101:JSTOR 87:books 3234:PMID 3199:PMID 3134:PMID 3060:PMID 3009:PMID 2930:ISBN 2815:PMID 2767:link 2747:ISBN 2289:< 2196:20.2 2098:7.41 1991:9.0% 1959:(TN) 1939:(FP) 1887:, 1871:= 10 1868:(FN) 1859:= 20 1856:(TP) 1847:= 30 1567:2 TP 181:and 172:and 164:and 156:and 148:The 73:news 3226:doi 3189:doi 3124:doi 3091:doi 3050:PMC 3040:doi 2999:PMC 2989:doi 2922:doi 2849:doi 2805:PMC 2797:doi 2793:309 2789:BMJ 2376:lim 2182:LR+ 2121:TNR 2115:FNR 2088:FPR 2082:TPR 2049:10% 2011:91% 1835:on 1503:LR− 1497:LR+ 1379:TNR 1373:FNR 1354:FPR 1348:TPR 1041:hit 849:NPV 835:FOR 763:NPV 645:NPV 552:NPV 477:PPV 463:FDR 347:PPV 250:PPV 211:In 158:NPV 154:PPV 56:by 3281:: 3263:. 3240:. 3232:. 3222:21 3220:. 3197:. 3185:45 3183:. 3179:. 3146:^ 3132:. 3120:33 3118:. 3114:. 3087:17 3085:. 3081:. 3058:. 3048:. 3036:14 3034:. 3030:. 3007:. 2997:. 2985:21 2983:. 2979:. 2953:. 2928:. 2901:. 2897:. 2878:. 2855:. 2845:27 2843:. 2839:. 2813:. 2803:. 2791:. 2787:. 2775:^ 2763:}} 2759:{{ 2745:. 2743:45 2674:. 2458:ln 2398:ln 2177:= 2149:= 2110:= 2077:= 2047:= 2009:= 1989:= 1980:, 1952:) 1932:) 1877:) 1817:≈ 1723:. 1633:TP 1628:= 1612:- 1603:= 1587:= 1562:= 1544:= 1516:= 1492:= 1459:PN 1453:TN 1448:= 1431:PP 1425:FP 1420:= 1395:= 1368:= 1343:= 1326:PN 1320:FN 1315:= 1298:PP 1292:TP 1287:= 1255:= 1229:TN 1224:= 1194:FP 1189:= 1120:FN 1115:= 1082:TP 1077:= 1064:, 994:= 978:, 933:, 929:, 631:: 623:, 325:, 219:. 193:. 3267:. 3248:. 3228:: 3205:. 3191:: 3140:. 3126:: 3099:. 3093:: 3066:. 3042:: 3015:. 2991:: 2964:. 2938:. 2924:: 2903:2 2882:. 2863:. 2851:: 2821:. 2799:: 2769:) 2755:. 2612:b 2590:a 2547:i 2543:n 2486:] 2480:b 2474:1 2470:a 2465:[ 2452:] 2446:) 2443:1 2437:k 2434:( 2426:) 2423:1 2414:( 2411:k 2405:[ 2380:k 2372:= 2367:i 2363:n 2337:i 2333:n 2312:k 2292:1 2185:/ 2118:/ 2085:/ 1839:) 1808:/ 1795:1 1793:F 1636:/ 1570:/ 1552:/ 1538:1 1536:F 1527:2 1524:/ 1500:/ 1456:/ 1428:/ 1403:/ 1376:/ 1351:/ 1323:/ 1295:/ 1263:/ 1260:P 1235:N 1232:/ 1200:N 1197:/ 1126:P 1123:/ 1088:P 1085:/ 1008:/ 878:= 867:+ 853:= 842:1 839:= 793:N 790:F 787:+ 784:N 781:T 776:N 773:T 767:= 724:) 713:1 710:( 707:+ 704:) 693:1 690:( 677:) 666:1 663:( 649:= 581:= 570:+ 556:= 506:= 495:+ 481:= 470:1 467:= 422:) 411:1 408:( 402:) 391:1 388:( 385:+ 351:= 279:= 268:+ 254:= 152:( 123:) 117:( 112:) 108:( 98:· 91:· 84:· 77:· 50:. 20:)

Index

Negative predictive value

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"Positive and negative predictive values"
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statistics
diagnostic tests
true positive
true negative
true positive rate
true negative rate
prevalence
Bayes' theorem
post-test probability
pre-test probability
information retrieval
precision
precision
true positive
gold standard
false positive

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