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Confidence interval

About: Confidence interval is a research topic. Over the lifetime, 19295 publications have been published within this topic receiving 870762 citations. The topic is also known as: CI & confidence intervals.


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Journal ArticleDOI
TL;DR: Intensive therapy effectively delays the onset and slows the progression of diabetic retinopathy, nephropathy, and neuropathy in patients with IDDM.
Abstract: Background Long-term microvascular and neurologic complications cause major morbidity and mortality in patients with insulin-dependent diabetes mellitus (IDDM). We examined whether intensive treatment with the goal of maintaining blood glucose concentrations close to the normal range could decrease the frequency and severity of these complications. Methods A total of 1441 patients with IDDM--726 with no retinopathy at base line (the primary-prevention cohort) and 715 with mild retinopathy (the secondary-intervention cohort) were randomly assigned to intensive therapy administered either with an external insulin pump or by three or more daily insulin injections and guided by frequent blood glucose monitoring or to conventional therapy with one or two daily insulin injections. The patients were followed for a mean of 6.5 years, and the appearance and progression of retinopathy and other complications were assessed regularly. Results In the primary-prevention cohort, intensive therapy reduced the adjusted mean risk for the development of retinopathy by 76 percent (95 percent confidence interval, 62 to 85 percent), as compared with conventional therapy. In the secondary-intervention cohort, intensive therapy slowed the progression of retinopathy by 54 percent (95 percent confidence interval, 39 to 66 percent) and reduced the development of proliferative or severe nonproliferative retinopathy by 47 percent (95 percent confidence interval, 14 to 67 percent). In the two cohorts combined, intensive therapy reduced the occurrence of microalbuminuria (urinary albumin excretion of > or = 40 mg per 24 hours) by 39 percent (95 percent confidence interval, 21 to 52 percent), that of albuminuria (urinary albumin excretion of > or = 300 mg per 24 hours) by 54 percent (95 percent confidence interval 19 to 74 percent), and that of clinical neuropathy by 60 percent (95 percent confidence interval, 38 to 74 percent). The chief adverse event associated with intensive therapy was a two-to-threefold increase in severe hypoglycemia. Conclusions Intensive therapy effectively delays the onset and slows the progression of diabetic retinopathy, nephropathy, and neuropathy in patients with IDDM.

21,148 citations

Journal ArticleDOI
TL;DR: In this article, a simple and robust estimator of regression coefficient β based on Kendall's rank correlation tau is studied, where the point estimator is the median of the set of slopes (Yj - Yi )/(tj-ti ) joining pairs of points with ti ≠ ti.
Abstract: The least squares estimator of a regression coefficient β is vulnerable to gross errors and the associated confidence interval is, in addition, sensitive to non-normality of the parent distribution. In this paper, a simple and robust (point as well as interval) estimator of β based on Kendall's [6] rank correlation tau is studied. The point estimator is the median of the set of slopes (Yj - Yi )/(tj-ti ) joining pairs of points with ti ≠ ti , and is unbiased. The confidence interval is also determined by two order statistics of this set of slopes. Various properties of these estimators are studied and compared with those of the least squares and some other nonparametric estimators.

8,409 citations

01 Mar 1948
TL;DR: The method provides means for the rapid test of parallelism of two curves and easy computation of relative potency with its confidence limits and its accuracy is commensurate with the nature of dose-per cent effect data.
Abstract: 1. A rapid graphic method for approximating the Median Effective Dose and the Slope of dose-per cent effect curves is presented. Confidence limits of both of these parameters for 19/20 probability are given by the method. In addition, confidence limits for any other probability or for a dose other than the Median Effective Dose are readily estimated. 2. The data are used throughout the method in their original form without transformation to logarithms and probits. 3. An effective means for plotting and using 0 and 100 per cent effects is provided. 4. The calculations have been simplified by means of nomographs to the extent that a slide rule is a convenience but not a necessity. 5. A simple means is provided for detecting a poorly fitted line or significantly heterogeneous data, In the former case, the line may be refitted; in the latter, the confidence limits are corrected for the degree of heterogeneity. 6. The method provides means for the rapid test of parallelism of two curves and easy computation of relative potency with its confidence limits. 7. Although the method is rapid (10-15 minutes), its accuracy is commensurate with the nature of dose-per cent effect data.

7,221 citations

Journal Article
TL;DR: In this article, a rapid graphic method for approximating the median effective dose and the slope of dose-per-cent effect curves is presented, and confidence limits of both of these parameters for 19/20 probability are given by the method.
Abstract: 1. A rapid graphic method for approximating the Median Effective Dose and the Slope of dose-per cent effect curves is presented. Confidence limits of both of these parameters for 19/20 probability are given by the method. In addition, confidence limits for any other probability or for a dose other than the Median Effective Dose are readily estimated. 2. The data are used throughout the method in their original form without transformation to logarithms and probits. 3. An effective means for plotting and using 0 and 100 per cent effects is provided. 4. The calculations have been simplified by means of nomographs to the extent that a slide rule is a convenience but not a necessity. 5. A simple means is provided for detecting a poorly fitted line or significantly heterogeneous data, In the former case, the line may be refitted; in the latter, the confidence limits are corrected for the degree of heterogeneity. 6. The method provides means for the rapid test of parallelism of two curves and easy computation of relative potency with its confidence limits. 7. Although the method is rapid (10-15 minutes), its accuracy is commensurate with the nature of dose-per cent effect data.

7,217 citations

Journal ArticleDOI
TL;DR: Findings indicate that low EPV can lead to major problems, and the regression coefficients were biased in both positive and negative directions, and paradoxical associations (significance in the wrong direction) were increased.

6,490 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20242
202316,033
202233,837
20212,157
20201,104
2019799