Assessing differences between two similar survival curves can pose a challenge for those without formal training in statistical interpretation; therefore, there has been an increased reliance on hazard ratios often to the exclusion of more-traditional survival measures. However, because a hazard ratio ...
The estimation of the hazard ratio in clinical trials and in meta-analysis. We consider the analysis of the results of controlled trials of (say) a certain new drug treatment against a standard treatment. In many cases, the only information which is conveniently available is (a) the initial ...
An assumption of proportional hazards regression is that the hazard ratio is constant over time.[1] HR 及其 95%置信区间由 Cox 回归模型计算得出。[2] H(t) 处于时间t时的风险;H0(t) 指的是基础风险(baseline hazard),所有预测变量为0时的风险;x1到xk指的是预测变量predictor variables wherex1⋯xkr...
三、比值比(OR——病例对照研究中 暴露因素与疾病的关联强度) 比值比(Odds ratio, OR):也称优势比、比数比、交叉乘积比,是病例对照研究中表示暴露与疾病之间关联强度的指标,比值(odds)是指某事物发生的概率与不发生的概率之比。比值比指病例组中暴露人数与非暴露人数的比值除以对照组中暴露人数与非暴露人数的比值。
Hazard ratio in clinical trials. ( Spruance et al, Antimicrobial Agents and Chemotherapy vol. 48 (8) pp. 2787, 2004). How the hazard ratio is computed There are two very similar ways of doing survival calculations: log-rank, and Mantel-Haenszel. Both are explained in chapter 3 of Machin...
Claudia Schmoor and Erika Graf 38.1 Introduction The hazard ratio is a useful measure to compare groups of patients with respect to a survival outcome. In the context of clinical trials, the terms ‘survival outcome’ or ‘survival time’ are used generically to denote the time ‘survived’ fr...
Hazard ratio in clinical trials. Antimicrob Agents Chemother 2004; 48: 2787–2792. Date of preparation: April 2009 7 NPR09/1107 What is...? series What are hazard ratios? This publication, along with the others in the series, is available on the internet at www.whatisseries.co.uk The ...
Clinical trialsRisk ratioElderlyThe hazard ratio is a measure of effect which is of paramount importance in etiological research, that is in studies aimed at assessing the strength of the causal relationship between a given treatment/exposure and a certain outcome. Despite the widespread use of the...
ANTIMICROBIALAGENTSANDCHEMOTHERAPY,Aug.2004,p.2787–2792Vol.48,No.8 0066-4804/04/$08.000DOI:10.1128/AAC.48.8.2787–2792.2004 Copyright©2004,AmericanSocietyforMicrobiology.AllRightsReserved. MINIREVIEW HazardRatioinClinicalTrials SpotswoodL.Spruance, 1 *JuliaE.Reid, 1 †MichaelGrace, 3 andMatthewS...
1 Hopefully the following dialogue will make these concepts more accessible for most of us, who have more rudimentary mathematical skills.Distinction from relative risk In contrast to the hazard ratio, the relative risk ratio is a measure of how many events What are hazard ratios?What are ...