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Hazard ratio

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587: 930:, they should be considered alongside other measures for interpretation of the treatment effect, e.g. the ratio of median times (median ratio) at which treatment and control group participants are at some endpoint. If the analogy of a race is applied, the hazard ratio is equivalent to the odds that an individual in the group with the higher hazard reaches the end of the race first. The probability of being first can be derived from the odds, which is the probability of being first divided by the probability of not being first: 47:
So, for a hazardous outcome (e.g., severe disease or death), an HR below 1 indicates that the treatment (e.g., vaccination) is protective against the outcome of interest. In other cases, an HR greater than 1 indicates the treatment is favorable. For example, if the outcome is actually favorable (e.g., accepting a job offer to end a spell of unemployment), an HR greater than 1 indicates that seeking a job is favorable to not seeking one (if "treatment" is defined as seeking a job).
1077:. A statistically important, but practically insignificant effect can produce a large hazard ratio, e.g. a treatment increasing the number of one-year survivors in a population from one in 10,000 to one in 1,000 has a hazard ratio of 10. It is unlikely that such a treatment would have had much impact on the median endpoint time ratio, which likely would have been close to unity, i.e. mortality was largely the same regardless of group membership and 614:(independent variable), e.g. death, remission of disease or contraction of disease. The curve represents the odds of an endpoint having occurred at each point in time (the hazard). The hazard ratio is simply the relationship between the instantaneous hazards in the two groups and represents, in a single number, the magnitude of distance between the Kaplan–Meier plots. 58:(ORs) in that RRs and ORs are cumulative over an entire study, using a defined endpoint, while HRs represent instantaneous risk over the study time period, or some subset thereof. Hazard ratios suffer somewhat less from selection bias with respect to the endpoints chosen and can indicate risks that happen before the endpoint. 46:
vaccination status was associated with significantly decreased risk for the composite of severe COVID-19 or mortality with a HR of 0.20 (95% CI, 0.17–0.22)." In essence, the hazard for the composite outcome was 80% lower among the vaccinated relative to those who were unvaccinated in the same study.
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By contrast, a treatment group in which 50% of infections are resolved after one week (versus 25% in the control) yields a hazard ratio of two. If it takes ten weeks for all cases in the treatment group and half of cases in the control group to resolve, the ten-week hazard ratio remains at two, but
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Treatment effect depends on the underlying disease related to survival function, not just the hazard ratio. Since the hazard ratio does not give us direct time-to-event information, researchers have to report median endpoint times and calculate the median endpoint time ratio by dividing the control
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exists between groups. For instance, a particularly risky surgery might result in the survival of a systematically more robust group who would have fared better under any of the competing treatment conditions, making it look as if the risky procedure was better. Follow-up time is also important. A
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Hazard ratios do not reflect a time unit of the study. The difference between hazard-based and time-based measures is akin to the difference between the odds of winning a race and the margin of victory. When a study reports one hazard ratio per time period, it is assumed that difference between
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is the estimate of treatment effect derived from the regression model. This hazard ratio, that is, the ratio between the predicted hazard for a member of one group and that for a member of the other group, is given by holding everything else constant, i.e. assuming proportionality of the hazard
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Hazard ratios are often treated as a ratio of death probabilities. For example, a hazard ratio of 2 is thought to mean that a group has twice the chance of dying than a comparison group. In the Cox-model, this can be shown to translate to the following relationship between group
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In its simplest form, the hazard ratio can be interpreted as the chance of an event occurring in the treatment arm divided by the chance of the event occurring in the control arm, or vice versa, of a study. The resolution of these endpoints are usually depicted using
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For a continuous explanatory variable, the same interpretation applies to a unit difference. Other HR models have different formulations and the interpretation of the parameter estimates differs accordingly.
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corresponding to the conditions characterised by two distinct levels of a treatment variable of interest. For example, in a clinical study of a drug, the treated population may die at twice the
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Elaimy, Ameer; Alexander R Mackay, Wayne T Lamoreaux, Robert K Fairbanks, John J Demakas, Barton S Cooke, Benjamin J Peressini, John T Holbrook, Christopher M Lee (5 July 2011).
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In the previous example, a hazard ratio of 2 corresponds to a 67% chance of an early death. The hazard ratio does not convey information about how soon the death will occur.
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While the median endpoint ratio is a relative speed measure, the hazard ratio is not. The relationship between treatment effect and the hazard ratio is given as
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are all possible causes of change in the hazard rate over time. For instance, a surgical procedure may have high early risk, but excellent long term outcomes.
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of the two groups, whereas a hazard ratio other than one indicates difference in hazard rates between groups. The researcher indicates the probability of this
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If the hazard ratio between groups remain constant, this is not a problem for interpretation. However, interpretation of hazard ratios become impossible when
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rates. The researchers' decision about when to follow up is arbitrary and may lead to very different reported hazard ratios.
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Najjar-Debbiny, R.; Gronich, N.; Weber, G.; Khoury, J.; Amar, M.; Stein, N.; Goldstein, L. H.; Saliba, W. (2 June 2022).
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The hazard ratio is the effect on this hazard rate of a difference, such as group membership (for example, treatment or
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of the control population. The hazard ratio would be 2, indicating a higher hazard of death from the treatment.
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groups was proportional. Hazard ratios become meaningless when this assumption of proportionality is not met.
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of the number of events per unit time divided by the number at risk, as the time interval approaches 0:
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For two groups that differ only in treatment condition, the ratio of the hazard functions is given by
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cancer treatment associated with better remission rates might on follow-up be associated with higher
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might then be used to assess the significance of any differences observed in these survival curves.
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The proportional hazards assumption for hazard ratio estimation is strong and often unreasonable.
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Clinical Trials: Study Design, Endpoints and Biomarkers, Drug Safety, and FDA and ICH Guidelines
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L. Douglas Case; Gretchen Kimmick, Electra D. Paskett, Kurt Lohmana, Robert Tucker (June 2002).
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and researchers provide a 95% confidence interval for the hazard ratio, e.g. derived from the
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If the proportional hazard assumption holds, a hazard ratio of one means equivalence in the
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For example, a scientific paper might use an HR to state something such as: "Adequate
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Spruance, Spotswood; Julia E. Reid, Michael Grace, Matthew Samore (August 2004).
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Intuitive Biostatistics: A Nonmathematical Guide to Statistical Thinking
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that treat the logarithm of the HR as a function of a baseline hazard
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is the hazard ratio). Therefore, with a hazard ratio of 2, if
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Conventionally, probabilities lower than 0.05 are considered
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Regression models are used to obtain hazard ratios and their
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The hazard ratio, treatment effect and time-based endpoints
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group median value by the treatment group median value.
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illustrating overall survival based on volume of brain
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Sas Survival Analysis Techniques for Medical Research
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Kleinbaum; Mitchel Klein (2005). 1231: 1229: 1227: 1225: 1223: 1672: 1615: 1613: 1576: 1449: 1439: 1323: 1261: 1161: 1085:the median endpoint time ratio is ten, a 2033:Preventable fraction among the unexposed 2029:Attributable fraction for the population 1544: 1542: 1518: 1390:Journal of the Royal Statistical Society 585: 2037:Preventable fraction for the population 2025:Attributable fraction among the exposed 1640: 1586:Survival Analysis: A Self-Learning Text 1512: 1487: 1485: 1483: 1220: 2252: 1699:Biostatistical Methods in Epidemiology 1695: 1689: 1646: 1619: 1610: 1301: 1299: 1297: 1295: 1722: 1655:. The Changing Face of Epidemiology. 1539: 1491: 1415: 1242:Antimicrobial Agents and Chemotherapy 912:{\displaystyle S_{1}(t)=0.2^{2}=0.04} 807:{\displaystyle S_{1}(t)=S_{0}(t)^{r}} 704:(one) in their confidence intervals. 2200:Correlation does not imply causation 2116:Animal testing on non-human primates 1498:. Academic Press. pp. 165–168. 1480: 1216:– via Elsevier Science Direct. 1626:. SAS Institute. pp. 111–150. 1383:"Regression-Models and Life-Tables" 1380: 1292: 708:The proportional hazards assumption 334:, male or female), as estimated by 13: 1552:Biostatistics: The Bare Essentials 1428:World Journal of Surgical Oncology 1374: 1013: 997: 942: 515:Such models are generally classed 311: 288: 245: 179: 151: 111: 14: 2286: 1238:"Hazard Ratio in Clinical Trials" 581: 519:models; the best known being the 1647:Hernán, Miguel (January 2010). 1254:10.1128/AAC.48.8.2787-2792.2004 1185:Flinn, C.; Heckman, J. (1982). 517:proportional hazards regression 2083:Pre- and post-test probability 1805:Patient and public involvement 1649:"The Hazards of Hazard Ratios" 1555:. PMPH-USA. pp. 283–287. 1178: 1129: 926:While hazard ratios allow for 887: 881: 841: 835: 795: 788: 772: 766: 521:Cox proportional hazards model 431: 425: 399: 393: 361: 355: 174: 168: 157: 136: 117: 100: 94: 1: 1325:10.1634/theoncologist.7-3-181 1123: 740:The hazard ratio and survival 700:hazard ratios cannot include 2210:Sex as a biological variable 1665:10.1097/EDE.0b013e3181c1ea43 1396:(2): 187–220. Archived from 1206:10.1016/0304-4076(82)90097-5 1142:Clinical Infectious Diseases 853:{\displaystyle S_{0}(t)=0.2} 604:Kaplan–Meier survival curves 7: 2174:Intention-to-treat analysis 2146:Analysis of clinical trials 2075:Specificity and sensitivity 1829:Randomized controlled trial 1113:Proportional hazards models 1092: 130:observed events in interval 10: 2291: 1070:{\displaystyle e^{\beta }} 657:from the Cox-model or the 546:{\displaystyle e^{\beta }} 254:{\displaystyle t+\Delta t} 50:Hazard ratios differ from 2218: 2183:Interpretation of results 2182: 2144: 2093: 2043: 2017: 1979: 1949: 1940: 1916:Nested case–control study 1866: 1813: 1760: 1702:. John Wiley & Sons. 1519:Motulsky, Harvey (2010). 698:Statistically significant 62:Definition and derivation 1785:Academic clinical trials 1696:Newman, Stephan (2003). 1589:(2 ed.). Springer. 1079:clinically insignificant 367:{\displaystyle h_{0}(t)} 320:{\displaystyle \Delta t} 297:{\displaystyle \Delta t} 2003:Relative risk reduction 1851:Adaptive clinical trial 1795:Evidence-based medicine 1778:Adaptive clinical trial 1194:Journal of Econometrics 1991:Number needed to treat 1441:10.1186/1477-7819-9-69 1392:. B (Methodological). 1087:clinically significant 1071: 1028: 975: 913: 860:(20% survived at time 854: 808: 690: 689:{\displaystyle \beta } 674:regression coefficient 651: 650:{\displaystyle \beta } 598: 597:. Elaimy et al. (2011) 567: 566:{\displaystyle \beta } 547: 506: 368: 321: 298: 275: 255: 226: 195: 31:) is the ratio of the 1995:Number needed to harm 1882:Cross-sectional study 1834:Scientific experiment 1790:Clinical study design 1620:Cantor, Alan (2003). 1072: 1029: 976: 914: 855: 809: 691: 652: 637:. For instance, the 633:associated with some 589: 568: 548: 507: 369: 322: 299: 276: 256: 227: 196: 1961:Cumulative incidence 1054: 985: 937: 868: 822: 753: 680: 641: 610:associated with the 557: 530: 381: 342: 308: 285: 265: 236: 216: 88: 68:confidence intervals 1868:Observational study 1800:Real world evidence 1754:experimental design 1492:Brody, Tom (2011). 1381:Cox, D. R. (1972). 1348:on 24 December 2019 1154:10.1093/cid/ciac443 2270:Statistical ratios 2265:Medical statistics 2154:Risk–benefit ratio 2121:First-in-man study 2071:Case fatality rate 1912:Case–control study 1886:Longitudinal study 1067: 1024: 971: 928:hypothesis testing 909: 850: 804: 747:survival functions 686: 670:standard deviation 647: 608:dependent variable 599: 591:Kaplan-Meier curve 563: 543: 502: 364: 317: 294: 271: 251: 222: 191: 124: 73:The instantaneous 37:rate per unit time 2275:Survival analysis 2247: 2246: 2195:Survivorship bias 2159:Systematic review 2126:Multicenter trial 2089: 2088: 2079:Likelihood-ratios 2051:Clinical endpoint 2019:Population impact 1973:Period prevalence 1750:Clinical research 1099:Survival analysis 1022: 969: 672:of the Cox-model 336:regression models 327:approaches zero. 274:{\displaystyle t} 225:{\displaystyle t} 186: 135: 131: 106: 21:survival analysis 2282: 2094:Trial/test types 1969:Point prevalence 1947: 1946: 1890:Ecological study 1873:EBM II-2 to II-3 1844:Open-label trial 1839:Blind experiment 1815:Controlled study 1743: 1736: 1729: 1720: 1719: 1714: 1713: 1693: 1687: 1686: 1676: 1644: 1638: 1637: 1617: 1608: 1607: 1605: 1603: 1580: 1574: 1573: 1571: 1569: 1546: 1537: 1536: 1516: 1510: 1509: 1489: 1478: 1477: 1471: 1463: 1453: 1443: 1419: 1413: 1412: 1410: 1408: 1402: 1387: 1378: 1372: 1371: 1365: 1357: 1355: 1353: 1344:. Archived from 1327: 1303: 1290: 1289: 1283: 1275: 1265: 1248:(8): 2787–2792. 1233: 1218: 1217: 1191: 1182: 1176: 1175: 1165: 1148:(3): e342–e349. 1133: 1076: 1074: 1073: 1068: 1066: 1065: 1033: 1031: 1030: 1025: 1023: 1021: 1020: 1019: 1003: 995: 980: 978: 977: 972: 970: 968: 954: 949: 948: 919:(4% survived at 918: 916: 915: 910: 902: 901: 880: 879: 859: 857: 856: 851: 834: 833: 813: 811: 810: 805: 803: 802: 787: 786: 765: 764: 695: 693: 692: 687: 656: 654: 653: 648: 572: 570: 569: 564: 552: 550: 549: 544: 542: 541: 511: 509: 508: 503: 498: 497: 491: 490: 481: 480: 462: 461: 452: 451: 424: 423: 414: 413: 373: 371: 370: 365: 354: 353: 326: 324: 323: 318: 303: 301: 300: 295: 280: 278: 277: 272: 260: 258: 257: 252: 231: 229: 228: 223: 200: 198: 197: 192: 187: 185: 177: 164: 133: 132: 129: 126: 123: 38: 2290: 2289: 2285: 2284: 2283: 2281: 2280: 2279: 2250: 2249: 2248: 2243: 2214: 2178: 2140: 2085: 2039: 2013: 1987:Risk difference 1975: 1936: 1870: 1862: 1817: 1809: 1773:Trial protocols 1756: 1747: 1717: 1710: 1694: 1690: 1645: 1641: 1634: 1618: 1611: 1601: 1599: 1597: 1581: 1577: 1567: 1565: 1563: 1547: 1540: 1533: 1517: 1513: 1506: 1490: 1481: 1465: 1464: 1420: 1416: 1406: 1404: 1403:on 20 June 2013 1400: 1385: 1379: 1375: 1359: 1358: 1351: 1349: 1304: 1293: 1277: 1276: 1234: 1221: 1189: 1183: 1179: 1134: 1130: 1126: 1095: 1061: 1057: 1055: 1052: 1051: 1044: 1012: 1011: 1004: 996: 994: 986: 983: 982: 958: 953: 941: 940: 938: 935: 934: 897: 893: 875: 871: 869: 866: 865: 829: 825: 823: 820: 819: 798: 794: 782: 778: 760: 756: 754: 751: 750: 742: 718:adverse effects 710: 681: 678: 677: 642: 639: 638: 584: 558: 555: 554: 537: 533: 531: 528: 527: 493: 492: 486: 482: 476: 472: 457: 453: 447: 443: 419: 415: 409: 408: 382: 379: 378: 349: 345: 343: 340: 339: 309: 306: 305: 286: 283: 282: 266: 263: 262: 237: 234: 233: 217: 214: 213: 178: 160: 128: 127: 125: 110: 89: 86: 85: 64: 36: 17: 12: 11: 5: 2288: 2278: 2277: 2272: 2267: 2262: 2245: 2244: 2242: 2241: 2238:List of topics 2234: 2227: 2219: 2216: 2215: 2213: 2212: 2207: 2202: 2197: 2192: 2190:Selection bias 2186: 2184: 2180: 2179: 2177: 2176: 2171: 2166: 2161: 2156: 2150: 2148: 2142: 2141: 2139: 2138: 2133: 2128: 2123: 2118: 2113: 2111:Animal testing 2108: 2103: 2097: 2095: 2091: 2090: 2087: 2086: 2063:Mortality rate 2049: 2047: 2041: 2040: 2023: 2021: 2015: 2014: 1985: 1983: 1977: 1976: 1955: 1953: 1944: 1938: 1937: 1935: 1934: 1929: 1924: 1919: 1909: 1908: 1907: 1902: 1892: 1878: 1876: 1864: 1863: 1861: 1860: 1859: 1858: 1856:Platform trial 1848: 1847: 1846: 1841: 1836: 1825: 1823: 1811: 1810: 1808: 1807: 1802: 1797: 1792: 1787: 1782: 1781: 1780: 1775: 1768:Clinical trial 1764: 1762: 1758: 1757: 1746: 1745: 1738: 1731: 1723: 1716: 1715: 1708: 1688: 1639: 1632: 1609: 1595: 1575: 1561: 1538: 1531: 1511: 1504: 1479: 1414: 1373: 1318:(3): 181–187. 1312:The Oncologist 1291: 1219: 1200:(1): 115–168. 1177: 1127: 1125: 1122: 1121: 1120: 1115: 1110: 1101: 1094: 1091: 1064: 1060: 1043: 1040: 1036: 1035: 1018: 1015: 1010: 1007: 1002: 999: 993: 990: 981:; conversely, 967: 964: 961: 957: 952: 947: 944: 908: 905: 900: 896: 892: 889: 886: 883: 878: 874: 849: 846: 843: 840: 837: 832: 828: 801: 797: 793: 790: 785: 781: 777: 774: 771: 768: 763: 759: 741: 738: 729:selection bias 709: 706: 685: 646: 635:test statistic 583: 582:Interpretation 580: 562: 540: 536: 513: 512: 501: 496: 489: 485: 479: 475: 471: 468: 465: 460: 456: 450: 446: 442: 439: 436: 433: 430: 427: 422: 418: 412: 407: 404: 401: 398: 395: 392: 389: 386: 363: 360: 357: 352: 348: 316: 313: 293: 290: 270: 250: 247: 244: 241: 221: 202: 201: 190: 184: 181: 176: 173: 170: 167: 163: 159: 156: 153: 150: 147: 144: 141: 138: 122: 119: 116: 113: 109: 105: 102: 99: 96: 93: 63: 60: 52:relative risks 15: 9: 6: 4: 3: 2: 2287: 2276: 2273: 2271: 2268: 2266: 2263: 2261: 2258: 2257: 2255: 2240: 2239: 2235: 2233: 2232: 2228: 2226: 2225: 2221: 2220: 2217: 2211: 2208: 2206: 2203: 2201: 2198: 2196: 2193: 2191: 2188: 2187: 2185: 2181: 2175: 2172: 2170: 2169:Meta-analysis 2167: 2165: 2162: 2160: 2157: 2155: 2152: 2151: 2149: 2147: 2143: 2137: 2136:Vaccine trial 2134: 2132: 2131:Seeding trial 2129: 2127: 2124: 2122: 2119: 2117: 2114: 2112: 2109: 2107: 2104: 2102: 2099: 2098: 2096: 2092: 2084: 2080: 2076: 2072: 2068: 2064: 2060: 2056: 2052: 2048: 2046: 2042: 2038: 2034: 2030: 2026: 2022: 2020: 2016: 2012: 2008: 2004: 2000: 1996: 1992: 1988: 1984: 1982: 1978: 1974: 1970: 1966: 1962: 1958: 1954: 1952: 1948: 1945: 1943: 1939: 1933: 1930: 1928: 1925: 1923: 1920: 1917: 1913: 1910: 1906: 1903: 1901: 1900:Retrospective 1898: 1897: 1896: 1893: 1891: 1887: 1883: 1880: 1879: 1877: 1874: 1869: 1865: 1857: 1854: 1853: 1852: 1849: 1845: 1842: 1840: 1837: 1835: 1832: 1831: 1830: 1827: 1826: 1824: 1821: 1820:EBM I to II-1 1816: 1812: 1806: 1803: 1801: 1798: 1796: 1793: 1791: 1788: 1786: 1783: 1779: 1776: 1774: 1771: 1770: 1769: 1766: 1765: 1763: 1759: 1755: 1751: 1744: 1739: 1737: 1732: 1730: 1725: 1724: 1721: 1711: 1709:9780471461609 1705: 1701: 1700: 1692: 1684: 1680: 1675: 1670: 1666: 1662: 1658: 1654: 1650: 1643: 1635: 1633:9781590471357 1629: 1625: 1624: 1616: 1614: 1598: 1596:9780387239187 1592: 1588: 1587: 1579: 1564: 1562:9781550093476 1558: 1554: 1553: 1545: 1543: 1534: 1532:9780199730063 1528: 1524: 1523: 1515: 1507: 1505:9780123919137 1501: 1497: 1496: 1488: 1486: 1484: 1475: 1469: 1461: 1457: 1452: 1447: 1442: 1437: 1433: 1429: 1425: 1418: 1399: 1395: 1391: 1384: 1377: 1369: 1363: 1347: 1343: 1339: 1335: 1331: 1326: 1321: 1317: 1313: 1309: 1302: 1300: 1298: 1296: 1287: 1281: 1273: 1269: 1264: 1259: 1255: 1251: 1247: 1243: 1239: 1232: 1230: 1228: 1226: 1224: 1215: 1211: 1207: 1203: 1199: 1195: 1188: 1181: 1173: 1169: 1164: 1159: 1155: 1151: 1147: 1143: 1139: 1132: 1128: 1119: 1118:Relative risk 1116: 1114: 1111: 1109: 1105: 1102: 1100: 1097: 1096: 1090: 1088: 1082: 1080: 1062: 1058: 1048: 1039: 1008: 1005: 991: 988: 965: 962: 959: 955: 950: 933: 932: 931: 929: 924: 922: 906: 903: 898: 894: 890: 884: 876: 872: 863: 847: 844: 838: 830: 826: 817: 799: 791: 783: 779: 775: 769: 761: 757: 748: 737: 735: 730: 725: 723: 719: 715: 714:Complications 705: 703: 699: 683: 675: 671: 667: 662: 660: 659:log-rank test 644: 636: 632: 628: 624: 619: 615: 613: 609: 605: 596: 592: 588: 579: 575: 560: 538: 534: 524: 522: 518: 499: 487: 483: 477: 473: 469: 466: 463: 458: 454: 448: 444: 440: 437: 434: 428: 420: 416: 405: 402: 396: 390: 387: 384: 377: 376: 375: 358: 350: 346: 337: 333: 328: 314: 291: 281:, divided by 268: 248: 242: 239: 219: 211: 207: 188: 182: 171: 165: 161: 154: 148: 145: 142: 139: 120: 114: 103: 97: 91: 84: 83: 82: 80: 76: 71: 69: 59: 57: 53: 48: 45: 40: 34: 30: 26: 22: 16:Medical ratio 2260:Epidemiology 2236: 2229: 2222: 2011:Hazard ratio 2010: 1895:Cohort study 1698: 1691: 1659:(1): 13–15. 1656: 1653:Epidemiology 1652: 1642: 1622: 1600:. Retrieved 1585: 1578: 1566:. Retrieved 1551: 1521: 1514: 1494: 1468:cite journal 1431: 1427: 1417: 1405:. Retrieved 1398:the original 1393: 1389: 1376: 1362:cite journal 1350:. Retrieved 1346:the original 1315: 1311: 1280:cite journal 1245: 1241: 1197: 1193: 1180: 1145: 1141: 1131: 1104:Failure rate 1089:difference. 1083: 1049: 1045: 1037: 925: 920: 861: 815: 743: 726: 722:late effects 711: 663: 620: 616: 600: 576: 525: 514: 329: 209: 205: 203: 72: 65: 49: 41: 33:hazard rates 28: 25:hazard ratio 24: 18: 2205:Null result 2164:Replication 2059:Infectivity 1981:Association 1932:Case report 1922:Case series 1905:Prospective 1108:Hazard rate 666:significant 631:probability 623:hazard rate 574:functions. 75:hazard rate 56:odds ratios 2254:Categories 2007:Odds ratio 1999:Risk ratio 1965:Prevalence 1951:Occurrence 1927:Case study 1602:7 December 1568:7 December 1434:(69): 69. 1407:5 December 1352:7 December 1124:References 595:metastases 54:(RRs) and 2067:Morbidity 2055:Virulence 1957:Incidence 1063:β 963:− 684:β 645:β 612:covariate 561:β 539:β 474:β 467:⋯ 445:β 438:α 388:⁡ 312:Δ 289:Δ 246:Δ 180:Δ 152:Δ 118:→ 112:Δ 2231:Glossary 2224:Category 2101:In vitro 1942:Measures 1761:Overview 1683:20010207 1460:21729314 1342:46520247 1334:12065789 1272:15273082 1214:16100294 1172:35653428 1093:See also 553:, where 44:COVID-19 2106:In vivo 1674:3653612 1451:3148547 1163:9214014 814:(where 734:relapse 676:, i.e. 332:control 77:is the 1706:  1681:  1671:  1630:  1593:  1559:  1529:  1502:  1458:  1448:  1340:  1332:  1270:  1263:478551 1260:  1212:  1170:  1160:  627:sample 204:where 134:  23:, the 2045:Other 1401:(PDF) 1386:(PDF) 1338:S2CID 1210:S2CID 1190:(PDF) 702:unity 304:, as 79:limit 1884:vs. 1752:and 1704:ISBN 1679:PMID 1628:ISBN 1604:2012 1591:ISBN 1570:2012 1557:ISBN 1527:ISBN 1500:ISBN 1474:link 1456:PMID 1409:2012 1368:link 1354:2012 1330:PMID 1286:link 1268:PMID 1168:PMID 1106:and 907:0.04 720:and 232:and 1669:PMC 1661:doi 1446:PMC 1436:doi 1320:doi 1258:PMC 1250:doi 1202:doi 1158:PMC 1150:doi 895:0.2 864:), 848:0.2 696:. 385:log 108:lim 19:In 2256:: 2081:, 2077:, 2073:, 2069:, 2065:, 2061:, 2057:, 2053:, 2035:, 2031:, 2027:, 2009:, 2005:, 2001:, 1997:, 1993:, 1989:, 1971:, 1967:, 1963:, 1959:, 1888:, 1677:. 1667:. 1657:21 1651:. 1612:^ 1541:^ 1482:^ 1470:}} 1466:{{ 1454:. 1444:. 1430:. 1426:. 1394:34 1388:. 1364:}} 1360:{{ 1336:. 1328:. 1314:. 1310:. 1294:^ 1282:}} 1278:{{ 1266:. 1256:. 1246:48 1244:. 1240:. 1222:^ 1208:. 1198:18 1196:. 1192:. 1166:. 1156:. 1146:76 1144:. 1140:. 1081:. 749:: 716:, 70:. 29:HR 1918:) 1914:( 1875:) 1871:( 1822:) 1818:( 1742:e 1735:t 1728:v 1712:. 1685:. 1663:: 1636:. 1606:. 1572:. 1535:. 1508:. 1476:) 1462:. 1438:: 1432:9 1411:. 1370:) 1356:. 1322:: 1316:7 1288:) 1274:. 1252:: 1204:: 1174:. 1152:: 1059:e 1034:. 1017:R 1014:H 1009:+ 1006:1 1001:R 998:H 992:= 989:P 966:P 960:1 956:P 951:= 946:R 943:H 921:t 904:= 899:2 891:= 888:) 885:t 882:( 877:1 873:S 862:t 845:= 842:) 839:t 836:( 831:0 827:S 816:r 800:r 796:) 792:t 789:( 784:0 780:S 776:= 773:) 770:t 767:( 762:1 758:S 535:e 500:. 495:) 488:k 484:X 478:k 470:+ 464:+ 459:1 455:X 449:1 441:+ 435:, 432:) 429:t 426:( 421:0 417:h 411:( 406:f 403:= 400:) 397:t 394:( 391:h 362:) 359:t 356:( 351:0 347:h 315:t 292:t 269:t 249:t 243:+ 240:t 220:t 210:t 208:( 206:N 189:, 183:t 175:) 172:t 169:( 166:N 162:/ 158:] 155:t 149:+ 146:t 143:, 140:t 137:[ 121:0 115:t 104:= 101:) 98:t 95:( 92:h 27:(

Index

survival analysis
hazard rates
COVID-19
relative risks
odds ratios
confidence intervals
hazard rate
limit
control
regression models
proportional hazards regression
Cox proportional hazards model

Kaplan-Meier curve
metastases
Kaplan–Meier survival curves
dependent variable
covariate
hazard rate
sample
probability
test statistic
log-rank test
significant
standard deviation
regression coefficient
Statistically significant
unity
Complications
adverse effects

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